diff mbox series

[v3,01/13] scmi: refactor the code to hide a channel from devices

Message ID 20230908025138.44405-2-takahiro.akashi@linaro.org
State Superseded
Headers show
Series firmware: scmi: add SCMI base protocol support | expand

Commit Message

AKASHI Takahiro Sept. 8, 2023, 2:51 a.m. UTC
The commit 85dc58289238 ("firmware: scmi: prepare uclass to pass channel
reference") added an explicit parameter, channel, but it seems to make
the code complex.

Hiding this parameter will allow for adding a generic (protocol-agnostic)
helper function, i.e. for PROTOCOL_VERSION, in a later patch.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
v3
* fix an issue on ST board (reported by Etienne)
  by taking care of cases where probed devices are children of
  SCMI protocol device (i.e. clock devices under CCF)
  See find_scmi_protocol_device().
* move "per_device_plato_auto" to a succeeding right patch
v2
* new patch
---
 drivers/clk/clk_scmi.c                    |  27 +---
 drivers/firmware/scmi/scmi_agent-uclass.c | 160 +++++++++++-----------
 drivers/power/regulator/scmi_regulator.c  |  27 +---
 drivers/reset/reset-scmi.c                |  19 +--
 include/scmi_agent.h                      |  15 +-
 5 files changed, 103 insertions(+), 145 deletions(-)

Comments

Etienne CARRIERE Sept. 8, 2023, 2:01 p.m. UTC | #1
Hello Akashi-san,

> 
> From: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Sent: Friday, September 8, 2023 04:51
>  
> The commit 85dc58289238 ("firmware: scmi: prepare uclass to pass channel
> reference") added an explicit parameter, channel, but it seems to make
> the code complex.
> 
> Hiding this parameter will allow for adding a generic (protocol-agnostic)
> helper function, i.e. for PROTOCOL_VERSION, in a later patch.
> 
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> ---
> v3
> * fix an issue on ST board (reported by Etienne)
>   by taking care of cases where probed devices are children of
>   SCMI protocol device (i.e. clock devices under CCF)
>   See find_scmi_protocol_device().
> * move "per_device_plato_auto" to a succeeding right patch
> v2
> * new patch
> ---
>  drivers/clk/clk_scmi.c                    |  27 +---
>  drivers/firmware/scmi/scmi_agent-uclass.c | 160 +++++++++++-----------
>  drivers/power/regulator/scmi_regulator.c  |  27 +---
>  drivers/reset/reset-scmi.c                |  19 +--
>  include/scmi_agent.h                      |  15 +-
>  5 files changed, 103 insertions(+), 145 deletions(-)
> 
> diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c
> index d172fed24c9d..34a49363a51a 100644
> --- a/drivers/clk/clk_scmi.c
> +++ b/drivers/clk/clk_scmi.c
> @@ -13,17 +13,8 @@
>  #include <asm/types.h>
>  #include <linux/clk-provider.h>
>  
> -/**
> - * struct scmi_clk_priv - Private data for SCMI clocks
> - * @channel: Reference to the SCMI channel to use
> - */
> -struct scmi_clk_priv {
> -       struct scmi_channel *channel;
> -};
> -
>  static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(dev);
>          struct scmi_clk_protocol_attr_out out;
>          struct scmi_msg msg = {
>                  .protocol_id = SCMI_PROTOCOL_ID_CLOCK,
> @@ -33,7 +24,7 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
>          };
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -44,7 +35,6 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
>  
>  static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(dev);
>          struct scmi_clk_attribute_in in = {
>                  .clock_id = clkid,
>          };
> @@ -59,7 +49,7 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
>          };
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -70,7 +60,6 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
>  
>  static int scmi_clk_gate(struct clk *clk, int enable)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
>          struct scmi_clk_state_in in = {
>                  .clock_id = clk->id,
>                  .attributes = enable,
> @@ -81,7 +70,7 @@ static int scmi_clk_gate(struct clk *clk, int enable)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(clk->dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -100,7 +89,6 @@ static int scmi_clk_disable(struct clk *clk)
>  
>  static ulong scmi_clk_get_rate(struct clk *clk)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
>          struct scmi_clk_rate_get_in in = {
>                  .clock_id = clk->id,
>          };
> @@ -110,7 +98,7 @@ static ulong scmi_clk_get_rate(struct clk *clk)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(clk->dev, &msg);
>          if (ret < 0)
>                  return ret;
>  
> @@ -123,7 +111,6 @@ static ulong scmi_clk_get_rate(struct clk *clk)
>  
>  static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
>          struct scmi_clk_rate_set_in in = {
>                  .clock_id = clk->id,
>                  .flags = SCMI_CLK_RATE_ROUND_CLOSEST,
> @@ -136,7 +123,7 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(clk->dev, &msg);
>          if (ret < 0)
>                  return ret;
>  
> @@ -149,12 +136,11 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
>  
>  static int scmi_clk_probe(struct udevice *dev)
>  {
> -       struct scmi_clk_priv *priv = dev_get_priv(dev);
>          struct clk *clk;
>          size_t num_clocks, i;
>          int ret;
>  
> -       ret = devm_scmi_of_get_channel(dev, &priv->channel);
> +       ret = devm_scmi_of_get_channel(dev);
>          if (ret)
>                  return ret;
>  
> @@ -205,5 +191,4 @@ U_BOOT_DRIVER(scmi_clock) = {
>          .id = UCLASS_CLK,
>          .ops = &scmi_clk_ops,
>          .probe = scmi_clk_probe,
> -       .priv_auto = sizeof(struct scmi_clk_priv *),
>  };
> diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c
> index 02de692d66f3..feb31809e715 100644
> --- a/drivers/firmware/scmi/scmi_agent-uclass.c
> +++ b/drivers/firmware/scmi/scmi_agent-uclass.c
> @@ -8,6 +8,7 @@
>  #include <common.h>
>  #include <dm.h>
>  #include <errno.h>
> +#include <scmi_agent.h>
>  #include <scmi_agent-uclass.h>
>  #include <scmi_protocols.h>
>  #include <dm/device_compat.h>
> @@ -51,77 +52,23 @@ int scmi_to_linux_errno(s32 scmi_code)
>          return -EPROTO;
>  }
>  
> -/*
> - * SCMI agent devices binds devices of various uclasses depeding on
> - * the FDT description. scmi_bind_protocol() is a generic bind sequence
> - * called by the uclass at bind stage, that is uclass post_bind.
> - */
> -static int scmi_bind_protocols(struct udevice *dev)

This patch removes function scmi_bind_protocols() whereas it should
be removed (actually moved) from patch PATCH v3 03/13
("firmware: scmi: move scmi_bind_protocols() backward").


> +static struct udevice *find_scmi_protocol_device(struct udevice *dev)
>  {
> -       int ret = 0;
> -       ofnode node;
> -       const char *name;
> -
> -       dev_for_each_subnode(node, dev) {
> -               struct driver *drv = NULL;
> -               u32 protocol_id;
> -
> -               if (!ofnode_is_enabled(node))
> -                       continue;
> -
> -               if (ofnode_read_u32(node, "reg", &protocol_id))
> -                       continue;
> +       struct udevice *parent = NULL, *protocol;
>  
> -               name = ofnode_get_name(node);
> -               switch (protocol_id) {
> -               case SCMI_PROTOCOL_ID_CLOCK:
> -                       if (CONFIG_IS_ENABLED(CLK_SCMI))
> -                               drv = DM_DRIVER_GET(scmi_clock);
> -                       break;
> -               case SCMI_PROTOCOL_ID_RESET_DOMAIN:
> -                       if (IS_ENABLED(CONFIG_RESET_SCMI))
> -                               drv = DM_DRIVER_GET(scmi_reset_domain);
> -                       break;
> -               case SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN:
> -                       if (IS_ENABLED(CONFIG_DM_REGULATOR_SCMI)) {
> -                               node = ofnode_find_subnode(node, "regulators");
> -                               if (!ofnode_valid(node)) {
> -                                       dev_err(dev, "no regulators node\n");
> -                                       return -ENXIO;
> -                               }
> -                               drv = DM_DRIVER_GET(scmi_voltage_domain);
> -                       }
> -                       break;
> -               default:
> -                       break;
> -               }
> -
> -               if (!drv) {
> -                       dev_dbg(dev, "Ignore unsupported SCMI protocol %#x\n",
> -                               protocol_id);
> -                       continue;
> -               }
> -
> -               ret = device_bind(dev, drv, name, NULL, node, NULL);
> -               if (ret)
> +       for (protocol = dev; protocol; protocol = parent) {
> +               parent = dev_get_parent(protocol);
> +               if (!parent ||
> +                   device_get_uclass_id(parent) == UCLASS_SCMI_AGENT)
>                          break;
>          }
>  
> -       return ret;
> -}
> -
> -static struct udevice *find_scmi_transport_device(struct udevice *dev)
> -{
> -       struct udevice *parent = dev;
> -
> -       do {
> -               parent = dev_get_parent(parent);
> -       } while (parent && device_get_uclass_id(parent) != UCLASS_SCMI_AGENT);
> -
> -       if (!parent)
> +       if (!parent) {
>                  dev_err(dev, "Invalid SCMI device, agent not found\n");
> +               return NULL;
> +       }
>  
> -       return parent;
> +       return protocol;
>  }
>  
>  static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
> @@ -129,43 +76,90 @@ static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
>          return (const struct scmi_agent_ops *)dev->driver->ops;
>  }
>  
> -int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
> +/**
> + * scmi_of_get_channel() - Get SCMI channel handle
> + *
> + * @dev:       SCMI agent device
> + * @channel:   Output reference to the SCMI channel upon success
> + *
> + * On return, @channel will be set.
> + * Return      0 on success and a negative errno on failure
> + */
> +static int scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
>  {
> -       struct udevice *parent;
> +       const struct scmi_agent_ops *ops;
>  
> -       parent = find_scmi_transport_device(dev);
> -       if (!parent)
> +       ops = transport_dev_ops(dev);
> +       if (ops->of_get_channel)
> +               return ops->of_get_channel(dev, channel);
> +       else
> +               return -EPROTONOSUPPORT;
> +}
> +
> +int devm_scmi_of_get_channel(struct udevice *dev)
> +{
> +       struct udevice *protocol;
> +       struct scmi_agent_proto_priv *priv;
> +       int ret;
> +
> +       protocol = find_scmi_protocol_device(dev);
> +       if (!protocol)
>                  return -ENODEV;
>  
> -       if (transport_dev_ops(parent)->of_get_channel)
> -               return transport_dev_ops(parent)->of_get_channel(parent, channel);
> +       priv = dev_get_parent_priv(protocol);
> +       ret = scmi_of_get_channel(protocol->parent, &priv->channel);
> +       if (ret == -EPROTONOSUPPORT) {
> +               /* Drivers without a get_channel operator don't need a channel ref */
> +               priv->channel = NULL;
>  
> -       /* Drivers without a get_channel operator don't need a channel ref */
> -       *channel = NULL;
> +               return 0;
> +       }
>  
> -       return 0;
> +       return ret;
>  }
>  
> -int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> -                         struct scmi_msg *msg)
> +/**
> + * scmi_process_msg() - Send and process an SCMI message
> + *
> + * Send a message to an SCMI server.
> + * Caller sets scmi_msg::out_msg_sz to the output message buffer size.
> + *
> + * @dev:       SCMI agent device
> + * @channel:   Communication channel for the device
> + * @msg:       Message structure reference
> + *
> + * On return, scmi_msg::out_msg_sz stores the response payload size.
> + * Return:     0 on success and a negative errno on failure
> + */
> +static int scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> +                           struct scmi_msg *msg)
>  {
>          const struct scmi_agent_ops *ops;
> -       struct udevice *parent;
>  
> -       parent = find_scmi_transport_device(dev);
> -       if (!parent)
> -               return -ENODEV;
> +       ops = transport_dev_ops(dev);
> +       if (ops->process_msg)
> +               return ops->process_msg(dev, channel, msg);
> +       else
> +               return -EPROTONOSUPPORT;
> +}
>  
> -       ops = transport_dev_ops(parent);
> +int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
> +{
> +       struct udevice *protocol;
> +       struct scmi_agent_proto_priv *priv;
>  
> -       if (ops->process_msg)
> -               return ops->process_msg(parent, channel, msg);
> +       protocol = find_scmi_protocol_device(dev);
> +       if (!protocol)
> +               return -ENODEV;
> +
> +       priv = dev_get_parent_priv(protocol);
>  
> -       return -EPROTONOSUPPORT;
> +       return scmi_process_msg(protocol->parent, priv->channel, msg);
>  }
>  
>  UCLASS_DRIVER(scmi_agent) = {
>          .id             = UCLASS_SCMI_AGENT,
>          .name           = "scmi_agent",
>          .post_bind      = scmi_bind_protocols,
> +       .per_child_auto = sizeof(struct scmi_agent_proto_priv *),
>  };
> diff --git a/drivers/power/regulator/scmi_regulator.c b/drivers/power/regulator/scmi_regulator.c
> index 801148036ff6..08918b20872c 100644
> --- a/drivers/power/regulator/scmi_regulator.c
> +++ b/drivers/power/regulator/scmi_regulator.c
> @@ -25,18 +25,9 @@ struct scmi_regulator_platdata {
>          u32 domain_id;
>  };
>  
> -/**
> - * struct scmi_regulator_priv - Private data for SCMI voltage regulator
> - * @channel: Reference to the SCMI channel to use
> - */
> -struct scmi_regulator_priv {
> -       struct scmi_channel *channel;
> -};
> -
>  static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
>  {
>          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
>          struct scmi_voltd_config_set_in in = {
>                  .domain_id = pdata->domain_id,
>                  .config = enable ? SCMI_VOLTD_CONFIG_ON : SCMI_VOLTD_CONFIG_OFF,
> @@ -47,7 +38,7 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -57,7 +48,6 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
>  static int scmi_voltd_get_enable(struct udevice *dev)
>  {
>          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
>          struct scmi_voltd_config_get_in in = {
>                  .domain_id = pdata->domain_id,
>          };
> @@ -67,7 +57,7 @@ static int scmi_voltd_get_enable(struct udevice *dev)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret < 0)
>                  return ret;
>  
> @@ -80,7 +70,6 @@ static int scmi_voltd_get_enable(struct udevice *dev)
>  
>  static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
>  {
> -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
>          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
>          struct scmi_voltd_level_set_in in = {
>                  .domain_id = pdata->domain_id,
> @@ -92,7 +81,7 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret < 0)
>                  return ret;
>  
> @@ -101,7 +90,6 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
>  
>  static int scmi_voltd_get_voltage_level(struct udevice *dev)
>  {
> -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
>          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
>          struct scmi_voltd_level_get_in in = {
>                  .domain_id = pdata->domain_id,
> @@ -112,7 +100,7 @@ static int scmi_voltd_get_voltage_level(struct udevice *dev)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(dev, &msg);
>          if (ret < 0)
>                  return ret;
>  
> @@ -140,7 +128,6 @@ static int scmi_regulator_of_to_plat(struct udevice *dev)
>  static int scmi_regulator_probe(struct udevice *dev)
>  {
>          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
>          struct scmi_voltd_attr_in in = { 0 };
>          struct scmi_voltd_attr_out out = { 0 };
>          struct scmi_msg scmi_msg = {
> @@ -153,14 +140,14 @@ static int scmi_regulator_probe(struct udevice *dev)
>          };
>          int ret;
>  
> -       ret = devm_scmi_of_get_channel(dev->parent, &priv->channel);
> +       ret = devm_scmi_of_get_channel(dev);
>          if (ret)
>                  return ret;
>  
>          /* Check voltage domain is known from SCMI server */
>          in.domain_id = pdata->domain_id;
>  
> -       ret = devm_scmi_process_msg(dev, priv->channel, &scmi_msg);
> +       ret = devm_scmi_process_msg(dev, &scmi_msg);
>          if (ret) {
>                  dev_err(dev, "Failed to query voltage domain %u: %d\n",
>                          pdata->domain_id, ret);
> @@ -184,7 +171,6 @@ U_BOOT_DRIVER(scmi_regulator) = {
>          .probe = scmi_regulator_probe,
>          .of_to_plat = scmi_regulator_of_to_plat,
>          .plat_auto = sizeof(struct scmi_regulator_platdata),
> -       .priv_auto = sizeof(struct scmi_regulator_priv *),
>  };
>  
>  static int scmi_regulator_bind(struct udevice *dev)
> @@ -209,4 +195,5 @@ U_BOOT_DRIVER(scmi_voltage_domain) = {
>          .name = "scmi_voltage_domain",
>          .id = UCLASS_NOP,
>          .bind = scmi_regulator_bind,
> +       .per_child_auto = sizeof(struct scmi_agent_proto_priv *),

I think this line is not needed. agent protocols private data is allocated
from .per_child_auto field set in scmi_agent-uclass.c above in this patch.


>  };
> diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c
> index 122556162ec3..b76711f0a8fb 100644
> --- a/drivers/reset/reset-scmi.c
> +++ b/drivers/reset/reset-scmi.c
> @@ -13,17 +13,8 @@
>  #include <scmi_protocols.h>
>  #include <asm/types.h>
>  
> -/**
> - * struct scmi_reset_priv - Private data for SCMI reset controller
> - * @channel: Reference to the SCMI channel to use
> - */
> -struct scmi_reset_priv {
> -       struct scmi_channel *channel;
> -};
> -
>  static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
>  {
> -       struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
>          struct scmi_rd_reset_in in = {
>                  .domain_id = rst->id,
>                  .flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
> @@ -35,7 +26,7 @@ static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
>                                            in, out);
>          int ret;
>  
> -       ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(rst->dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -54,7 +45,6 @@ static int scmi_reset_deassert(struct reset_ctl *rst)
>  
>  static int scmi_reset_request(struct reset_ctl *rst)
>  {
> -       struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
>          struct scmi_rd_attr_in in = {
>                  .domain_id = rst->id,
>          };
> @@ -68,7 +58,7 @@ static int scmi_reset_request(struct reset_ctl *rst)
>           * We don't really care about the attribute, just check
>           * the reset domain exists.
>           */
> -       ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
> +       ret = devm_scmi_process_msg(rst->dev, &msg);
>          if (ret)
>                  return ret;
>  
> @@ -83,9 +73,7 @@ static const struct reset_ops scmi_reset_domain_ops = {
>  
>  static int scmi_reset_probe(struct udevice *dev)
>  {
> -       struct scmi_reset_priv *priv = dev_get_priv(dev);
> -
> -       return devm_scmi_of_get_channel(dev, &priv->channel);
> +       return devm_scmi_of_get_channel(dev);
>  }
>  
>  U_BOOT_DRIVER(scmi_reset_domain) = {
> @@ -93,5 +81,4 @@ U_BOOT_DRIVER(scmi_reset_domain) = {
>          .id = UCLASS_RESET,
>          .ops = &scmi_reset_domain_ops,
>          .probe = scmi_reset_probe,
> -       .priv_auto = sizeof(struct scmi_reset_priv *),
>  };
> diff --git a/include/scmi_agent.h b/include/scmi_agent.h
> index ee6286366df7..577892029ff8 100644
> --- a/include/scmi_agent.h
> +++ b/include/scmi_agent.h
> @@ -15,6 +15,14 @@
>  struct udevice;
>  struct scmi_channel;
>  
> +/**
> + * struct scmi_agent_proto_priv - Private data in device for SCMI agent
> + * @channel: Reference to the SCMI channel to use
> + */
> +struct scmi_agent_proto_priv {
> +       struct scmi_channel *channel;
> +};
> +
>  /*
>   * struct scmi_msg - Context of a SCMI message sent and the response received
>   *
> @@ -49,10 +57,9 @@ struct scmi_msg {
>   * devm_scmi_of_get_channel() - Get SCMI channel handle from SCMI agent DT node
>   *
>   * @dev:       Device requesting a channel
> - * @channel:   Output reference to the SCMI channel upon success
>   * @return 0 on success and a negative errno on failure
>   */
> -int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel);
> +int devm_scmi_of_get_channel(struct udevice *dev);
>  
>  /**
>   * devm_scmi_process_msg() - Send and process an SCMI message
> @@ -62,12 +69,10 @@ int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
>   * On return, scmi_msg::out_msg_sz stores the response payload size.
>   *
>   * @dev:       SCMI device
> - * @channel:   Communication channel for the device
>   * @msg:       Message structure reference
>   * Return: 0 on success and a negative errno on failure
>   */
> -int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> -                         struct scmi_msg *msg);
> +int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg);
>  
>  /**
>   * scmi_to_linux_errno() - Convert an SCMI error code into a Linux errno code
> -- 
> 2.34.1
>
AKASHI Takahiro Sept. 11, 2023, 6:43 a.m. UTC | #2
Hi Etienne,

Thank you gain for your review.

On Fri, Sep 08, 2023 at 02:01:51PM +0000, Etienne CARRIERE wrote:
> Hello Akashi-san,
> 
> > 
> > From: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Sent: Friday, September 8, 2023 04:51
> >  
> > The commit 85dc58289238 ("firmware: scmi: prepare uclass to pass channel
> > reference") added an explicit parameter, channel, but it seems to make
> > the code complex.
> > 
> > Hiding this parameter will allow for adding a generic (protocol-agnostic)
> > helper function, i.e. for PROTOCOL_VERSION, in a later patch.
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Reviewed-by: Simon Glass <sjg@chromium.org>
> > ---
> > v3
> > * fix an issue on ST board (reported by Etienne)
> >   by taking care of cases where probed devices are children of
> >   SCMI protocol device (i.e. clock devices under CCF)
> >   See find_scmi_protocol_device().
> > * move "per_device_plato_auto" to a succeeding right patch
> > v2
> > * new patch
> > ---
> >  drivers/clk/clk_scmi.c                    |  27 +---
> >  drivers/firmware/scmi/scmi_agent-uclass.c | 160 +++++++++++-----------
> >  drivers/power/regulator/scmi_regulator.c  |  27 +---
> >  drivers/reset/reset-scmi.c                |  19 +--
> >  include/scmi_agent.h                      |  15 +-
> >  5 files changed, 103 insertions(+), 145 deletions(-)
> > 
> > diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c
> > index d172fed24c9d..34a49363a51a 100644
> > --- a/drivers/clk/clk_scmi.c
> > +++ b/drivers/clk/clk_scmi.c
> > @@ -13,17 +13,8 @@
> >  #include <asm/types.h>
> >  #include <linux/clk-provider.h>
> >  
> > -/**
> > - * struct scmi_clk_priv - Private data for SCMI clocks
> > - * @channel: Reference to the SCMI channel to use
> > - */
> > -struct scmi_clk_priv {
> > -       struct scmi_channel *channel;
> > -};
> > -
> >  static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(dev);
> >          struct scmi_clk_protocol_attr_out out;
> >          struct scmi_msg msg = {
> >                  .protocol_id = SCMI_PROTOCOL_ID_CLOCK,
> > @@ -33,7 +24,7 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
> >          };
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -44,7 +35,6 @@ static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
> >  
> >  static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(dev);
> >          struct scmi_clk_attribute_in in = {
> >                  .clock_id = clkid,
> >          };
> > @@ -59,7 +49,7 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
> >          };
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -70,7 +60,6 @@ static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
> >  
> >  static int scmi_clk_gate(struct clk *clk, int enable)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
> >          struct scmi_clk_state_in in = {
> >                  .clock_id = clk->id,
> >                  .attributes = enable,
> > @@ -81,7 +70,7 @@ static int scmi_clk_gate(struct clk *clk, int enable)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(clk->dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -100,7 +89,6 @@ static int scmi_clk_disable(struct clk *clk)
> >  
> >  static ulong scmi_clk_get_rate(struct clk *clk)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
> >          struct scmi_clk_rate_get_in in = {
> >                  .clock_id = clk->id,
> >          };
> > @@ -110,7 +98,7 @@ static ulong scmi_clk_get_rate(struct clk *clk)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(clk->dev, &msg);
> >          if (ret < 0)
> >                  return ret;
> >  
> > @@ -123,7 +111,6 @@ static ulong scmi_clk_get_rate(struct clk *clk)
> >  
> >  static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
> >          struct scmi_clk_rate_set_in in = {
> >                  .clock_id = clk->id,
> >                  .flags = SCMI_CLK_RATE_ROUND_CLOSEST,
> > @@ -136,7 +123,7 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(clk->dev, &msg);
> >          if (ret < 0)
> >                  return ret;
> >  
> > @@ -149,12 +136,11 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
> >  
> >  static int scmi_clk_probe(struct udevice *dev)
> >  {
> > -       struct scmi_clk_priv *priv = dev_get_priv(dev);
> >          struct clk *clk;
> >          size_t num_clocks, i;
> >          int ret;
> >  
> > -       ret = devm_scmi_of_get_channel(dev, &priv->channel);
> > +       ret = devm_scmi_of_get_channel(dev);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -205,5 +191,4 @@ U_BOOT_DRIVER(scmi_clock) = {
> >          .id = UCLASS_CLK,
> >          .ops = &scmi_clk_ops,
> >          .probe = scmi_clk_probe,
> > -       .priv_auto = sizeof(struct scmi_clk_priv *),
> >  };
> > diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c
> > index 02de692d66f3..feb31809e715 100644
> > --- a/drivers/firmware/scmi/scmi_agent-uclass.c
> > +++ b/drivers/firmware/scmi/scmi_agent-uclass.c
> > @@ -8,6 +8,7 @@
> >  #include <common.h>
> >  #include <dm.h>
> >  #include <errno.h>
> > +#include <scmi_agent.h>
> >  #include <scmi_agent-uclass.h>
> >  #include <scmi_protocols.h>
> >  #include <dm/device_compat.h>
> > @@ -51,77 +52,23 @@ int scmi_to_linux_errno(s32 scmi_code)
> >          return -EPROTO;
> >  }
> >  
> > -/*
> > - * SCMI agent devices binds devices of various uclasses depeding on
> > - * the FDT description. scmi_bind_protocol() is a generic bind sequence
> > - * called by the uclass at bind stage, that is uclass post_bind.
> > - */
> > -static int scmi_bind_protocols(struct udevice *dev)
> 
> This patch removes function scmi_bind_protocols() whereas it should
> be removed (actually moved) from patch PATCH v3 03/13
> ("firmware: scmi: move scmi_bind_protocols() backward").

You're right. I accidentally remove the function in refactoring.
It will be restored again here to keep 03/13 correct.

> 
> > +static struct udevice *find_scmi_protocol_device(struct udevice *dev)
> >  {
> > -       int ret = 0;
> > -       ofnode node;
> > -       const char *name;
> > -
> > -       dev_for_each_subnode(node, dev) {
> > -               struct driver *drv = NULL;
> > -               u32 protocol_id;
> > -
> > -               if (!ofnode_is_enabled(node))
> > -                       continue;
> > -
> > -               if (ofnode_read_u32(node, "reg", &protocol_id))
> > -                       continue;
> > +       struct udevice *parent = NULL, *protocol;
> >  
> > -               name = ofnode_get_name(node);
> > -               switch (protocol_id) {
> > -               case SCMI_PROTOCOL_ID_CLOCK:
> > -                       if (CONFIG_IS_ENABLED(CLK_SCMI))
> > -                               drv = DM_DRIVER_GET(scmi_clock);
> > -                       break;
> > -               case SCMI_PROTOCOL_ID_RESET_DOMAIN:
> > -                       if (IS_ENABLED(CONFIG_RESET_SCMI))
> > -                               drv = DM_DRIVER_GET(scmi_reset_domain);
> > -                       break;
> > -               case SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN:
> > -                       if (IS_ENABLED(CONFIG_DM_REGULATOR_SCMI)) {
> > -                               node = ofnode_find_subnode(node, "regulators");
> > -                               if (!ofnode_valid(node)) {
> > -                                       dev_err(dev, "no regulators node\n");
> > -                                       return -ENXIO;
> > -                               }
> > -                               drv = DM_DRIVER_GET(scmi_voltage_domain);
> > -                       }
> > -                       break;
> > -               default:
> > -                       break;
> > -               }
> > -
> > -               if (!drv) {
> > -                       dev_dbg(dev, "Ignore unsupported SCMI protocol %#x\n",
> > -                               protocol_id);
> > -                       continue;
> > -               }
> > -
> > -               ret = device_bind(dev, drv, name, NULL, node, NULL);
> > -               if (ret)
> > +       for (protocol = dev; protocol; protocol = parent) {
> > +               parent = dev_get_parent(protocol);
> > +               if (!parent ||
> > +                   device_get_uclass_id(parent) == UCLASS_SCMI_AGENT)
> >                          break;
> >          }
> >  
> > -       return ret;
> > -}
> > -
> > -static struct udevice *find_scmi_transport_device(struct udevice *dev)
> > -{
> > -       struct udevice *parent = dev;
> > -
> > -       do {
> > -               parent = dev_get_parent(parent);
> > -       } while (parent && device_get_uclass_id(parent) != UCLASS_SCMI_AGENT);
> > -
> > -       if (!parent)
> > +       if (!parent) {
> >                  dev_err(dev, "Invalid SCMI device, agent not found\n");
> > +               return NULL;
> > +       }
> >  
> > -       return parent;
> > +       return protocol;
> >  }
> >  
> >  static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
> > @@ -129,43 +76,90 @@ static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
> >          return (const struct scmi_agent_ops *)dev->driver->ops;
> >  }
> >  
> > -int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
> > +/**
> > + * scmi_of_get_channel() - Get SCMI channel handle
> > + *
> > + * @dev:       SCMI agent device
> > + * @channel:   Output reference to the SCMI channel upon success
> > + *
> > + * On return, @channel will be set.
> > + * Return      0 on success and a negative errno on failure
> > + */
> > +static int scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
> >  {
> > -       struct udevice *parent;
> > +       const struct scmi_agent_ops *ops;
> >  
> > -       parent = find_scmi_transport_device(dev);
> > -       if (!parent)
> > +       ops = transport_dev_ops(dev);
> > +       if (ops->of_get_channel)
> > +               return ops->of_get_channel(dev, channel);
> > +       else
> > +               return -EPROTONOSUPPORT;
> > +}
> > +
> > +int devm_scmi_of_get_channel(struct udevice *dev)
> > +{
> > +       struct udevice *protocol;
> > +       struct scmi_agent_proto_priv *priv;
> > +       int ret;
> > +
> > +       protocol = find_scmi_protocol_device(dev);
> > +       if (!protocol)
> >                  return -ENODEV;
> >  
> > -       if (transport_dev_ops(parent)->of_get_channel)
> > -               return transport_dev_ops(parent)->of_get_channel(parent, channel);
> > +       priv = dev_get_parent_priv(protocol);
> > +       ret = scmi_of_get_channel(protocol->parent, &priv->channel);
> > +       if (ret == -EPROTONOSUPPORT) {
> > +               /* Drivers without a get_channel operator don't need a channel ref */
> > +               priv->channel = NULL;
> >  
> > -       /* Drivers without a get_channel operator don't need a channel ref */
> > -       *channel = NULL;
> > +               return 0;
> > +       }
> >  
> > -       return 0;
> > +       return ret;
> >  }
> >  
> > -int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> > -                         struct scmi_msg *msg)
> > +/**
> > + * scmi_process_msg() - Send and process an SCMI message
> > + *
> > + * Send a message to an SCMI server.
> > + * Caller sets scmi_msg::out_msg_sz to the output message buffer size.
> > + *
> > + * @dev:       SCMI agent device
> > + * @channel:   Communication channel for the device
> > + * @msg:       Message structure reference
> > + *
> > + * On return, scmi_msg::out_msg_sz stores the response payload size.
> > + * Return:     0 on success and a negative errno on failure
> > + */
> > +static int scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> > +                           struct scmi_msg *msg)
> >  {
> >          const struct scmi_agent_ops *ops;
> > -       struct udevice *parent;
> >  
> > -       parent = find_scmi_transport_device(dev);
> > -       if (!parent)
> > -               return -ENODEV;
> > +       ops = transport_dev_ops(dev);
> > +       if (ops->process_msg)
> > +               return ops->process_msg(dev, channel, msg);
> > +       else
> > +               return -EPROTONOSUPPORT;
> > +}
> >  
> > -       ops = transport_dev_ops(parent);
> > +int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
> > +{
> > +       struct udevice *protocol;
> > +       struct scmi_agent_proto_priv *priv;
> >  
> > -       if (ops->process_msg)
> > -               return ops->process_msg(parent, channel, msg);
> > +       protocol = find_scmi_protocol_device(dev);
> > +       if (!protocol)
> > +               return -ENODEV;
> > +
> > +       priv = dev_get_parent_priv(protocol);
> >  
> > -       return -EPROTONOSUPPORT;
> > +       return scmi_process_msg(protocol->parent, priv->channel, msg);
> >  }
> >  
> >  UCLASS_DRIVER(scmi_agent) = {
> >          .id             = UCLASS_SCMI_AGENT,
> >          .name           = "scmi_agent",
> >          .post_bind      = scmi_bind_protocols,
> > +       .per_child_auto = sizeof(struct scmi_agent_proto_priv *),
> >  };
> > diff --git a/drivers/power/regulator/scmi_regulator.c b/drivers/power/regulator/scmi_regulator.c
> > index 801148036ff6..08918b20872c 100644
> > --- a/drivers/power/regulator/scmi_regulator.c
> > +++ b/drivers/power/regulator/scmi_regulator.c
> > @@ -25,18 +25,9 @@ struct scmi_regulator_platdata {
> >          u32 domain_id;
> >  };
> >  
> > -/**
> > - * struct scmi_regulator_priv - Private data for SCMI voltage regulator
> > - * @channel: Reference to the SCMI channel to use
> > - */
> > -struct scmi_regulator_priv {
> > -       struct scmi_channel *channel;
> > -};
> > -
> >  static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
> >  {
> >          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> > -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
> >          struct scmi_voltd_config_set_in in = {
> >                  .domain_id = pdata->domain_id,
> >                  .config = enable ? SCMI_VOLTD_CONFIG_ON : SCMI_VOLTD_CONFIG_OFF,
> > @@ -47,7 +38,7 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -57,7 +48,6 @@ static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
> >  static int scmi_voltd_get_enable(struct udevice *dev)
> >  {
> >          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> > -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
> >          struct scmi_voltd_config_get_in in = {
> >                  .domain_id = pdata->domain_id,
> >          };
> > @@ -67,7 +57,7 @@ static int scmi_voltd_get_enable(struct udevice *dev)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret < 0)
> >                  return ret;
> >  
> > @@ -80,7 +70,6 @@ static int scmi_voltd_get_enable(struct udevice *dev)
> >  
> >  static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
> >  {
> > -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
> >          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> >          struct scmi_voltd_level_set_in in = {
> >                  .domain_id = pdata->domain_id,
> > @@ -92,7 +81,7 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret < 0)
> >                  return ret;
> >  
> > @@ -101,7 +90,6 @@ static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
> >  
> >  static int scmi_voltd_get_voltage_level(struct udevice *dev)
> >  {
> > -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
> >          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> >          struct scmi_voltd_level_get_in in = {
> >                  .domain_id = pdata->domain_id,
> > @@ -112,7 +100,7 @@ static int scmi_voltd_get_voltage_level(struct udevice *dev)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(dev, &msg);
> >          if (ret < 0)
> >                  return ret;
> >  
> > @@ -140,7 +128,6 @@ static int scmi_regulator_of_to_plat(struct udevice *dev)
> >  static int scmi_regulator_probe(struct udevice *dev)
> >  {
> >          struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
> > -       struct scmi_regulator_priv *priv = dev_get_priv(dev);
> >          struct scmi_voltd_attr_in in = { 0 };
> >          struct scmi_voltd_attr_out out = { 0 };
> >          struct scmi_msg scmi_msg = {
> > @@ -153,14 +140,14 @@ static int scmi_regulator_probe(struct udevice *dev)
> >          };
> >          int ret;
> >  
> > -       ret = devm_scmi_of_get_channel(dev->parent, &priv->channel);
> > +       ret = devm_scmi_of_get_channel(dev);
> >          if (ret)
> >                  return ret;
> >  
> >          /* Check voltage domain is known from SCMI server */
> >          in.domain_id = pdata->domain_id;
> >  
> > -       ret = devm_scmi_process_msg(dev, priv->channel, &scmi_msg);
> > +       ret = devm_scmi_process_msg(dev, &scmi_msg);
> >          if (ret) {
> >                  dev_err(dev, "Failed to query voltage domain %u: %d\n",
> >                          pdata->domain_id, ret);
> > @@ -184,7 +171,6 @@ U_BOOT_DRIVER(scmi_regulator) = {
> >          .probe = scmi_regulator_probe,
> >          .of_to_plat = scmi_regulator_of_to_plat,
> >          .plat_auto = sizeof(struct scmi_regulator_platdata),
> > -       .priv_auto = sizeof(struct scmi_regulator_priv *),
> >  };
> >  
> >  static int scmi_regulator_bind(struct udevice *dev)
> > @@ -209,4 +195,5 @@ U_BOOT_DRIVER(scmi_voltage_domain) = {
> >          .name = "scmi_voltage_domain",
> >          .id = UCLASS_NOP,
> >          .bind = scmi_regulator_bind,
> > +       .per_child_auto = sizeof(struct scmi_agent_proto_priv *),
> 
> I think this line is not needed. agent protocols private data is allocated
> from .per_child_auto field set in scmi_agent-uclass.c above in this patch.

Yes, I will delete it.

-Takahiro Akashi

> 
> 
> >  };
> > diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c
> > index 122556162ec3..b76711f0a8fb 100644
> > --- a/drivers/reset/reset-scmi.c
> > +++ b/drivers/reset/reset-scmi.c
> > @@ -13,17 +13,8 @@
> >  #include <scmi_protocols.h>
> >  #include <asm/types.h>
> >  
> > -/**
> > - * struct scmi_reset_priv - Private data for SCMI reset controller
> > - * @channel: Reference to the SCMI channel to use
> > - */
> > -struct scmi_reset_priv {
> > -       struct scmi_channel *channel;
> > -};
> > -
> >  static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
> >  {
> > -       struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
> >          struct scmi_rd_reset_in in = {
> >                  .domain_id = rst->id,
> >                  .flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
> > @@ -35,7 +26,7 @@ static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
> >                                            in, out);
> >          int ret;
> >  
> > -       ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(rst->dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -54,7 +45,6 @@ static int scmi_reset_deassert(struct reset_ctl *rst)
> >  
> >  static int scmi_reset_request(struct reset_ctl *rst)
> >  {
> > -       struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
> >          struct scmi_rd_attr_in in = {
> >                  .domain_id = rst->id,
> >          };
> > @@ -68,7 +58,7 @@ static int scmi_reset_request(struct reset_ctl *rst)
> >           * We don't really care about the attribute, just check
> >           * the reset domain exists.
> >           */
> > -       ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
> > +       ret = devm_scmi_process_msg(rst->dev, &msg);
> >          if (ret)
> >                  return ret;
> >  
> > @@ -83,9 +73,7 @@ static const struct reset_ops scmi_reset_domain_ops = {
> >  
> >  static int scmi_reset_probe(struct udevice *dev)
> >  {
> > -       struct scmi_reset_priv *priv = dev_get_priv(dev);
> > -
> > -       return devm_scmi_of_get_channel(dev, &priv->channel);
> > +       return devm_scmi_of_get_channel(dev);
> >  }
> >  
> >  U_BOOT_DRIVER(scmi_reset_domain) = {
> > @@ -93,5 +81,4 @@ U_BOOT_DRIVER(scmi_reset_domain) = {
> >          .id = UCLASS_RESET,
> >          .ops = &scmi_reset_domain_ops,
> >          .probe = scmi_reset_probe,
> > -       .priv_auto = sizeof(struct scmi_reset_priv *),
> >  };
> > diff --git a/include/scmi_agent.h b/include/scmi_agent.h
> > index ee6286366df7..577892029ff8 100644
> > --- a/include/scmi_agent.h
> > +++ b/include/scmi_agent.h
> > @@ -15,6 +15,14 @@
> >  struct udevice;
> >  struct scmi_channel;
> >  
> > +/**
> > + * struct scmi_agent_proto_priv - Private data in device for SCMI agent
> > + * @channel: Reference to the SCMI channel to use
> > + */
> > +struct scmi_agent_proto_priv {
> > +       struct scmi_channel *channel;
> > +};
> > +
> >  /*
> >   * struct scmi_msg - Context of a SCMI message sent and the response received
> >   *
> > @@ -49,10 +57,9 @@ struct scmi_msg {
> >   * devm_scmi_of_get_channel() - Get SCMI channel handle from SCMI agent DT node
> >   *
> >   * @dev:       Device requesting a channel
> > - * @channel:   Output reference to the SCMI channel upon success
> >   * @return 0 on success and a negative errno on failure
> >   */
> > -int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel);
> > +int devm_scmi_of_get_channel(struct udevice *dev);
> >  
> >  /**
> >   * devm_scmi_process_msg() - Send and process an SCMI message
> > @@ -62,12 +69,10 @@ int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
> >   * On return, scmi_msg::out_msg_sz stores the response payload size.
> >   *
> >   * @dev:       SCMI device
> > - * @channel:   Communication channel for the device
> >   * @msg:       Message structure reference
> >   * Return: 0 on success and a negative errno on failure
> >   */
> > -int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
> > -                         struct scmi_msg *msg);
> > +int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg);
> >  
> >  /**
> >   * scmi_to_linux_errno() - Convert an SCMI error code into a Linux errno code
> > -- 
> > 2.34.1
> >
diff mbox series

Patch

diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c
index d172fed24c9d..34a49363a51a 100644
--- a/drivers/clk/clk_scmi.c
+++ b/drivers/clk/clk_scmi.c
@@ -13,17 +13,8 @@ 
 #include <asm/types.h>
 #include <linux/clk-provider.h>
 
-/**
- * struct scmi_clk_priv - Private data for SCMI clocks
- * @channel: Reference to the SCMI channel to use
- */
-struct scmi_clk_priv {
-	struct scmi_channel *channel;
-};
-
 static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(dev);
 	struct scmi_clk_protocol_attr_out out;
 	struct scmi_msg msg = {
 		.protocol_id = SCMI_PROTOCOL_ID_CLOCK,
@@ -33,7 +24,7 @@  static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
 	};
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret)
 		return ret;
 
@@ -44,7 +35,6 @@  static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
 
 static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(dev);
 	struct scmi_clk_attribute_in in = {
 		.clock_id = clkid,
 	};
@@ -59,7 +49,7 @@  static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
 	};
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret)
 		return ret;
 
@@ -70,7 +60,6 @@  static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
 
 static int scmi_clk_gate(struct clk *clk, int enable)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
 	struct scmi_clk_state_in in = {
 		.clock_id = clk->id,
 		.attributes = enable,
@@ -81,7 +70,7 @@  static int scmi_clk_gate(struct clk *clk, int enable)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(clk->dev, &msg);
 	if (ret)
 		return ret;
 
@@ -100,7 +89,6 @@  static int scmi_clk_disable(struct clk *clk)
 
 static ulong scmi_clk_get_rate(struct clk *clk)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
 	struct scmi_clk_rate_get_in in = {
 		.clock_id = clk->id,
 	};
@@ -110,7 +98,7 @@  static ulong scmi_clk_get_rate(struct clk *clk)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(clk->dev, &msg);
 	if (ret < 0)
 		return ret;
 
@@ -123,7 +111,6 @@  static ulong scmi_clk_get_rate(struct clk *clk)
 
 static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(clk->dev);
 	struct scmi_clk_rate_set_in in = {
 		.clock_id = clk->id,
 		.flags = SCMI_CLK_RATE_ROUND_CLOSEST,
@@ -136,7 +123,7 @@  static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(clk->dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(clk->dev, &msg);
 	if (ret < 0)
 		return ret;
 
@@ -149,12 +136,11 @@  static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
 
 static int scmi_clk_probe(struct udevice *dev)
 {
-	struct scmi_clk_priv *priv = dev_get_priv(dev);
 	struct clk *clk;
 	size_t num_clocks, i;
 	int ret;
 
-	ret = devm_scmi_of_get_channel(dev, &priv->channel);
+	ret = devm_scmi_of_get_channel(dev);
 	if (ret)
 		return ret;
 
@@ -205,5 +191,4 @@  U_BOOT_DRIVER(scmi_clock) = {
 	.id = UCLASS_CLK,
 	.ops = &scmi_clk_ops,
 	.probe = scmi_clk_probe,
-	.priv_auto = sizeof(struct scmi_clk_priv *),
 };
diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c
index 02de692d66f3..feb31809e715 100644
--- a/drivers/firmware/scmi/scmi_agent-uclass.c
+++ b/drivers/firmware/scmi/scmi_agent-uclass.c
@@ -8,6 +8,7 @@ 
 #include <common.h>
 #include <dm.h>
 #include <errno.h>
+#include <scmi_agent.h>
 #include <scmi_agent-uclass.h>
 #include <scmi_protocols.h>
 #include <dm/device_compat.h>
@@ -51,77 +52,23 @@  int scmi_to_linux_errno(s32 scmi_code)
 	return -EPROTO;
 }
 
-/*
- * SCMI agent devices binds devices of various uclasses depeding on
- * the FDT description. scmi_bind_protocol() is a generic bind sequence
- * called by the uclass at bind stage, that is uclass post_bind.
- */
-static int scmi_bind_protocols(struct udevice *dev)
+static struct udevice *find_scmi_protocol_device(struct udevice *dev)
 {
-	int ret = 0;
-	ofnode node;
-	const char *name;
-
-	dev_for_each_subnode(node, dev) {
-		struct driver *drv = NULL;
-		u32 protocol_id;
-
-		if (!ofnode_is_enabled(node))
-			continue;
-
-		if (ofnode_read_u32(node, "reg", &protocol_id))
-			continue;
+	struct udevice *parent = NULL, *protocol;
 
-		name = ofnode_get_name(node);
-		switch (protocol_id) {
-		case SCMI_PROTOCOL_ID_CLOCK:
-			if (CONFIG_IS_ENABLED(CLK_SCMI))
-				drv = DM_DRIVER_GET(scmi_clock);
-			break;
-		case SCMI_PROTOCOL_ID_RESET_DOMAIN:
-			if (IS_ENABLED(CONFIG_RESET_SCMI))
-				drv = DM_DRIVER_GET(scmi_reset_domain);
-			break;
-		case SCMI_PROTOCOL_ID_VOLTAGE_DOMAIN:
-			if (IS_ENABLED(CONFIG_DM_REGULATOR_SCMI)) {
-				node = ofnode_find_subnode(node, "regulators");
-				if (!ofnode_valid(node)) {
-					dev_err(dev, "no regulators node\n");
-					return -ENXIO;
-				}
-				drv = DM_DRIVER_GET(scmi_voltage_domain);
-			}
-			break;
-		default:
-			break;
-		}
-
-		if (!drv) {
-			dev_dbg(dev, "Ignore unsupported SCMI protocol %#x\n",
-				protocol_id);
-			continue;
-		}
-
-		ret = device_bind(dev, drv, name, NULL, node, NULL);
-		if (ret)
+	for (protocol = dev; protocol; protocol = parent) {
+		parent = dev_get_parent(protocol);
+		if (!parent ||
+		    device_get_uclass_id(parent) == UCLASS_SCMI_AGENT)
 			break;
 	}
 
-	return ret;
-}
-
-static struct udevice *find_scmi_transport_device(struct udevice *dev)
-{
-	struct udevice *parent = dev;
-
-	do {
-		parent = dev_get_parent(parent);
-	} while (parent && device_get_uclass_id(parent) != UCLASS_SCMI_AGENT);
-
-	if (!parent)
+	if (!parent) {
 		dev_err(dev, "Invalid SCMI device, agent not found\n");
+		return NULL;
+	}
 
-	return parent;
+	return protocol;
 }
 
 static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
@@ -129,43 +76,90 @@  static const struct scmi_agent_ops *transport_dev_ops(struct udevice *dev)
 	return (const struct scmi_agent_ops *)dev->driver->ops;
 }
 
-int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
+/**
+ * scmi_of_get_channel() - Get SCMI channel handle
+ *
+ * @dev:	SCMI agent device
+ * @channel:	Output reference to the SCMI channel upon success
+ *
+ * On return, @channel will be set.
+ * Return	0 on success and a negative errno on failure
+ */
+static int scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
 {
-	struct udevice *parent;
+	const struct scmi_agent_ops *ops;
 
-	parent = find_scmi_transport_device(dev);
-	if (!parent)
+	ops = transport_dev_ops(dev);
+	if (ops->of_get_channel)
+		return ops->of_get_channel(dev, channel);
+	else
+		return -EPROTONOSUPPORT;
+}
+
+int devm_scmi_of_get_channel(struct udevice *dev)
+{
+	struct udevice *protocol;
+	struct scmi_agent_proto_priv *priv;
+	int ret;
+
+	protocol = find_scmi_protocol_device(dev);
+	if (!protocol)
 		return -ENODEV;
 
-	if (transport_dev_ops(parent)->of_get_channel)
-		return transport_dev_ops(parent)->of_get_channel(parent, channel);
+	priv = dev_get_parent_priv(protocol);
+	ret = scmi_of_get_channel(protocol->parent, &priv->channel);
+	if (ret == -EPROTONOSUPPORT) {
+		/* Drivers without a get_channel operator don't need a channel ref */
+		priv->channel = NULL;
 
-	/* Drivers without a get_channel operator don't need a channel ref */
-	*channel = NULL;
+		return 0;
+	}
 
-	return 0;
+	return ret;
 }
 
-int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
-			  struct scmi_msg *msg)
+/**
+ * scmi_process_msg() - Send and process an SCMI message
+ *
+ * Send a message to an SCMI server.
+ * Caller sets scmi_msg::out_msg_sz to the output message buffer size.
+ *
+ * @dev:	SCMI agent device
+ * @channel:	Communication channel for the device
+ * @msg:	Message structure reference
+ *
+ * On return, scmi_msg::out_msg_sz stores the response payload size.
+ * Return:	0 on success and a negative errno on failure
+ */
+static int scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
+			    struct scmi_msg *msg)
 {
 	const struct scmi_agent_ops *ops;
-	struct udevice *parent;
 
-	parent = find_scmi_transport_device(dev);
-	if (!parent)
-		return -ENODEV;
+	ops = transport_dev_ops(dev);
+	if (ops->process_msg)
+		return ops->process_msg(dev, channel, msg);
+	else
+		return -EPROTONOSUPPORT;
+}
 
-	ops = transport_dev_ops(parent);
+int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
+{
+	struct udevice *protocol;
+	struct scmi_agent_proto_priv *priv;
 
-	if (ops->process_msg)
-		return ops->process_msg(parent, channel, msg);
+	protocol = find_scmi_protocol_device(dev);
+	if (!protocol)
+		return -ENODEV;
+
+	priv = dev_get_parent_priv(protocol);
 
-	return -EPROTONOSUPPORT;
+	return scmi_process_msg(protocol->parent, priv->channel, msg);
 }
 
 UCLASS_DRIVER(scmi_agent) = {
 	.id		= UCLASS_SCMI_AGENT,
 	.name		= "scmi_agent",
 	.post_bind	= scmi_bind_protocols,
+	.per_child_auto	= sizeof(struct scmi_agent_proto_priv *),
 };
diff --git a/drivers/power/regulator/scmi_regulator.c b/drivers/power/regulator/scmi_regulator.c
index 801148036ff6..08918b20872c 100644
--- a/drivers/power/regulator/scmi_regulator.c
+++ b/drivers/power/regulator/scmi_regulator.c
@@ -25,18 +25,9 @@  struct scmi_regulator_platdata {
 	u32 domain_id;
 };
 
-/**
- * struct scmi_regulator_priv - Private data for SCMI voltage regulator
- * @channel: Reference to the SCMI channel to use
- */
-struct scmi_regulator_priv {
-	struct scmi_channel *channel;
-};
-
 static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
 {
 	struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
-	struct scmi_regulator_priv *priv = dev_get_priv(dev);
 	struct scmi_voltd_config_set_in in = {
 		.domain_id = pdata->domain_id,
 		.config = enable ? SCMI_VOLTD_CONFIG_ON : SCMI_VOLTD_CONFIG_OFF,
@@ -47,7 +38,7 @@  static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret)
 		return ret;
 
@@ -57,7 +48,6 @@  static int scmi_voltd_set_enable(struct udevice *dev, bool enable)
 static int scmi_voltd_get_enable(struct udevice *dev)
 {
 	struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
-	struct scmi_regulator_priv *priv = dev_get_priv(dev);
 	struct scmi_voltd_config_get_in in = {
 		.domain_id = pdata->domain_id,
 	};
@@ -67,7 +57,7 @@  static int scmi_voltd_get_enable(struct udevice *dev)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret < 0)
 		return ret;
 
@@ -80,7 +70,6 @@  static int scmi_voltd_get_enable(struct udevice *dev)
 
 static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
 {
-	struct scmi_regulator_priv *priv = dev_get_priv(dev);
 	struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
 	struct scmi_voltd_level_set_in in = {
 		.domain_id = pdata->domain_id,
@@ -92,7 +81,7 @@  static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret < 0)
 		return ret;
 
@@ -101,7 +90,6 @@  static int scmi_voltd_set_voltage_level(struct udevice *dev, int uV)
 
 static int scmi_voltd_get_voltage_level(struct udevice *dev)
 {
-	struct scmi_regulator_priv *priv = dev_get_priv(dev);
 	struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
 	struct scmi_voltd_level_get_in in = {
 		.domain_id = pdata->domain_id,
@@ -112,7 +100,7 @@  static int scmi_voltd_get_voltage_level(struct udevice *dev)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(dev, &msg);
 	if (ret < 0)
 		return ret;
 
@@ -140,7 +128,6 @@  static int scmi_regulator_of_to_plat(struct udevice *dev)
 static int scmi_regulator_probe(struct udevice *dev)
 {
 	struct scmi_regulator_platdata *pdata = dev_get_plat(dev);
-	struct scmi_regulator_priv *priv = dev_get_priv(dev);
 	struct scmi_voltd_attr_in in = { 0 };
 	struct scmi_voltd_attr_out out = { 0 };
 	struct scmi_msg scmi_msg = {
@@ -153,14 +140,14 @@  static int scmi_regulator_probe(struct udevice *dev)
 	};
 	int ret;
 
-	ret = devm_scmi_of_get_channel(dev->parent, &priv->channel);
+	ret = devm_scmi_of_get_channel(dev);
 	if (ret)
 		return ret;
 
 	/* Check voltage domain is known from SCMI server */
 	in.domain_id = pdata->domain_id;
 
-	ret = devm_scmi_process_msg(dev, priv->channel, &scmi_msg);
+	ret = devm_scmi_process_msg(dev, &scmi_msg);
 	if (ret) {
 		dev_err(dev, "Failed to query voltage domain %u: %d\n",
 			pdata->domain_id, ret);
@@ -184,7 +171,6 @@  U_BOOT_DRIVER(scmi_regulator) = {
 	.probe = scmi_regulator_probe,
 	.of_to_plat = scmi_regulator_of_to_plat,
 	.plat_auto = sizeof(struct scmi_regulator_platdata),
-	.priv_auto = sizeof(struct scmi_regulator_priv *),
 };
 
 static int scmi_regulator_bind(struct udevice *dev)
@@ -209,4 +195,5 @@  U_BOOT_DRIVER(scmi_voltage_domain) = {
 	.name = "scmi_voltage_domain",
 	.id = UCLASS_NOP,
 	.bind = scmi_regulator_bind,
+	.per_child_auto = sizeof(struct scmi_agent_proto_priv *),
 };
diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c
index 122556162ec3..b76711f0a8fb 100644
--- a/drivers/reset/reset-scmi.c
+++ b/drivers/reset/reset-scmi.c
@@ -13,17 +13,8 @@ 
 #include <scmi_protocols.h>
 #include <asm/types.h>
 
-/**
- * struct scmi_reset_priv - Private data for SCMI reset controller
- * @channel: Reference to the SCMI channel to use
- */
-struct scmi_reset_priv {
-	struct scmi_channel *channel;
-};
-
 static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
 {
-	struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
 	struct scmi_rd_reset_in in = {
 		.domain_id = rst->id,
 		.flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
@@ -35,7 +26,7 @@  static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
 					  in, out);
 	int ret;
 
-	ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(rst->dev, &msg);
 	if (ret)
 		return ret;
 
@@ -54,7 +45,6 @@  static int scmi_reset_deassert(struct reset_ctl *rst)
 
 static int scmi_reset_request(struct reset_ctl *rst)
 {
-	struct scmi_reset_priv *priv = dev_get_priv(rst->dev);
 	struct scmi_rd_attr_in in = {
 		.domain_id = rst->id,
 	};
@@ -68,7 +58,7 @@  static int scmi_reset_request(struct reset_ctl *rst)
 	 * We don't really care about the attribute, just check
 	 * the reset domain exists.
 	 */
-	ret = devm_scmi_process_msg(rst->dev, priv->channel, &msg);
+	ret = devm_scmi_process_msg(rst->dev, &msg);
 	if (ret)
 		return ret;
 
@@ -83,9 +73,7 @@  static const struct reset_ops scmi_reset_domain_ops = {
 
 static int scmi_reset_probe(struct udevice *dev)
 {
-	struct scmi_reset_priv *priv = dev_get_priv(dev);
-
-	return devm_scmi_of_get_channel(dev, &priv->channel);
+	return devm_scmi_of_get_channel(dev);
 }
 
 U_BOOT_DRIVER(scmi_reset_domain) = {
@@ -93,5 +81,4 @@  U_BOOT_DRIVER(scmi_reset_domain) = {
 	.id = UCLASS_RESET,
 	.ops = &scmi_reset_domain_ops,
 	.probe = scmi_reset_probe,
-	.priv_auto = sizeof(struct scmi_reset_priv *),
 };
diff --git a/include/scmi_agent.h b/include/scmi_agent.h
index ee6286366df7..577892029ff8 100644
--- a/include/scmi_agent.h
+++ b/include/scmi_agent.h
@@ -15,6 +15,14 @@ 
 struct udevice;
 struct scmi_channel;
 
+/**
+ * struct scmi_agent_proto_priv - Private data in device for SCMI agent
+ * @channel: Reference to the SCMI channel to use
+ */
+struct scmi_agent_proto_priv {
+	struct scmi_channel *channel;
+};
+
 /*
  * struct scmi_msg - Context of a SCMI message sent and the response received
  *
@@ -49,10 +57,9 @@  struct scmi_msg {
  * devm_scmi_of_get_channel() - Get SCMI channel handle from SCMI agent DT node
  *
  * @dev:	Device requesting a channel
- * @channel:	Output reference to the SCMI channel upon success
  * @return 0 on success and a negative errno on failure
  */
-int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel);
+int devm_scmi_of_get_channel(struct udevice *dev);
 
 /**
  * devm_scmi_process_msg() - Send and process an SCMI message
@@ -62,12 +69,10 @@  int devm_scmi_of_get_channel(struct udevice *dev, struct scmi_channel **channel)
  * On return, scmi_msg::out_msg_sz stores the response payload size.
  *
  * @dev:	SCMI device
- * @channel:	Communication channel for the device
  * @msg:	Message structure reference
  * Return: 0 on success and a negative errno on failure
  */
-int devm_scmi_process_msg(struct udevice *dev, struct scmi_channel *channel,
-			  struct scmi_msg *msg);
+int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg);
 
 /**
  * scmi_to_linux_errno() - Convert an SCMI error code into a Linux errno code