diff mbox series

[6/7] pinctrl: Implementation of the generic scmi-pinctrl driver

Message ID 20231215-pinctrl-scmi-v1-6-0fe35e4611f7@nxp.com
State New
Headers show
Series firmware: arm_scmi: Add SCMI v3.2 pincontrol protocol basic support | expand

Commit Message

Peng Fan (OSS) Dec. 15, 2023, 11:56 a.m. UTC
From: Peng Fan <peng.fan@nxp.com>

scmi-pinctrl driver implements pinctrl driver interface and using
SCMI protocol to redirect messages from pinctrl subsystem SDK to
SCMI platform firmware, which does the changes in HW.

Co-developed-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 MAINTAINERS                    |   1 +
 drivers/pinctrl/Kconfig        |  11 ++
 drivers/pinctrl/Makefile       |   1 +
 drivers/pinctrl/pinctrl-scmi.c | 403 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 416 insertions(+)

Comments

Cristian Marussi Dec. 22, 2023, 4:35 p.m. UTC | #1
On Fri, Dec 15, 2023 at 07:56:34PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
> 
> scmi-pinctrl driver implements pinctrl driver interface and using
> SCMI protocol to redirect messages from pinctrl subsystem SDK to
> SCMI platform firmware, which does the changes in HW.
> 

[CC: Akashi which was interested in this series]

This generic driver still works fine for me as of now in my emulated
setup using the generic SCMI bindings as in the initial Oleksii example
and a dummy driver consumer for this pins, BUT there is still an open
issue as reported by Akashi previously ..see below.

> Co-developed-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
> Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@epam.com>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---
>  MAINTAINERS                    |   1 +
>  drivers/pinctrl/Kconfig        |  11 ++
>  drivers/pinctrl/Makefile       |   1 +
>  drivers/pinctrl/pinctrl-scmi.c | 403 +++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 416 insertions(+)
 
 [snip]

> +static const struct pinmux_ops pinctrl_scmi_pinmux_ops = {
> +	.request = pinctrl_scmi_request,
> +	.free = pinctrl_scmi_free,
> +	.get_functions_count = pinctrl_scmi_get_functions_count,
> +	.get_function_name = pinctrl_scmi_get_function_name,
> +	.get_function_groups = pinctrl_scmi_get_function_groups,
> +	.set_mux = pinctrl_scmi_func_set_mux,
> +};
> +
> +static int pinctrl_scmi_pinconf_get(struct pinctrl_dev *pctldev, unsigned int _pin,
> +				    unsigned long *config)
> +{
> +	int ret;
> +	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
> +	enum pin_config_param config_type;
> +	unsigned long config_value;
> +
> +	if (!config)
> +		return -EINVAL;
> +
> +	config_type = pinconf_to_config_param(*config);

This config types that are packed/unpacked from the generic Pinctrl
subsystem have also to be mapped/umapped, here and below, to the SCMI
ones since they are slightly different/.

IOW SCMI V3.2 Table_24 in the spec, which defines Pins Config Types as
understood by an SCMI platform FW is NOT exactly mapping to the enum
pin_config_param used by Pinctrl in its pinconf_to_config so you risk
passing a config_type to the SCMI fw that does NOT mean at all what
intended...if the FW is compliant with SCMI.

> +
> +	ret = pinctrl_ops->config_get(pmx->ph, _pin, PIN_TYPE, config_type, &config_value);
> +	if (ret)
> +		return ret;
> +
> +	*config = pinconf_to_config_packed(config_type, config_value);
> +
> +	return 0;
> +}
> +
> +static int pinctrl_scmi_pinconf_set(struct pinctrl_dev *pctldev,
> +				    unsigned int _pin,
> +				    unsigned long *configs,
> +				    unsigned int num_configs)
> +{
> +	int ret;
> +	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
> +
> +	if (!configs || !num_configs)
> +		return -EINVAL;
> +

Same here, as said in the previous patch about pinctrl protocol, you
should pack/unpack and map/unmap from Pinctrl packed configs and types
to SCMI types and unpacked config/values, to fix the mismatch between
Pinctrl and SCMI types and also to avoid the usage of Pinctrl helpers to
extract the types from the SCMI protocol layer so that we can keep it
agnostic in these regards.

Thanks,
Cristian
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 8d971adeee22..0ca47b9c9f55 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21172,6 +21172,7 @@  F:	drivers/clk/clk-sc[mp]i.c
 F:	drivers/cpufreq/sc[mp]i-cpufreq.c
 F:	drivers/firmware/arm_scmi/
 F:	drivers/firmware/arm_scpi.c
+F:	drivers/pinctrl/pinctrl-scmi.c
 F:	drivers/pmdomain/arm/
 F:	drivers/powercap/arm_scmi_powercap.c
 F:	drivers/regulator/scmi-regulator.c
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 8163a5983166..27b26e428f60 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -432,6 +432,17 @@  config PINCTRL_ROCKCHIP
 	help
           This support pinctrl and GPIO driver for Rockchip SoCs.
 
+config PINCTRL_SCMI
+	tristate "Pinctrl driver using SCMI protocol interface"
+	depends on ARM_SCMI_PROTOCOL || COMPILE_TEST
+	select PINMUX
+	select GENERIC_PINCONF
+	help
+	  This driver provides support for pinctrl which is controlled
+	  by firmware that implements the SCMI interface.
+	  It uses SCMI Message Protocol to interact with the
+	  firmware providing all the pinctrl controls.
+
 config PINCTRL_SINGLE
 	tristate "One-register-per-pin type device tree based pinctrl driver"
 	depends on OF
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 1071f301cc70..ba755ed2d46c 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -44,6 +44,7 @@  obj-$(CONFIG_PINCTRL_PIC32)	+= pinctrl-pic32.o
 obj-$(CONFIG_PINCTRL_PISTACHIO)	+= pinctrl-pistachio.o
 obj-$(CONFIG_PINCTRL_RK805)	+= pinctrl-rk805.o
 obj-$(CONFIG_PINCTRL_ROCKCHIP)	+= pinctrl-rockchip.o
+obj-$(CONFIG_PINCTRL_SCMI)	+= pinctrl-scmi.o
 obj-$(CONFIG_PINCTRL_SINGLE)	+= pinctrl-single.o
 obj-$(CONFIG_PINCTRL_ST) 	+= pinctrl-st.o
 obj-$(CONFIG_PINCTRL_STMFX) 	+= pinctrl-stmfx.o
diff --git a/drivers/pinctrl/pinctrl-scmi.c b/drivers/pinctrl/pinctrl-scmi.c
new file mode 100644
index 000000000000..0710ce9a1b42
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-scmi.c
@@ -0,0 +1,403 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Power Interface (SCMI) Protocol based pinctrl driver
+ *
+ * Copyright (C) 2023 EPAM
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/scmi_protocol.h>
+#include <linux/slab.h>
+
+#include <linux/pinctrl/machine.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+
+#include "pinctrl-utils.h"
+#include "core.h"
+#include "pinconf.h"
+
+#define DRV_NAME "scmi-pinctrl"
+
+static const struct scmi_pinctrl_proto_ops *pinctrl_ops;
+
+struct scmi_pinctrl_funcs {
+	unsigned int num_groups;
+	const char **groups;
+};
+
+struct scmi_pinctrl {
+	struct device *dev;
+	struct scmi_protocol_handle *ph;
+	struct pinctrl_dev *pctldev;
+	struct pinctrl_desc pctl_desc;
+	struct scmi_pinctrl_funcs *functions;
+	unsigned int nr_functions;
+	char **groups;
+	unsigned int nr_groups;
+	struct pinctrl_pin_desc *pins;
+	unsigned int nr_pins;
+};
+
+static int pinctrl_scmi_get_groups_count(struct pinctrl_dev *pctldev)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->count_get(pmx->ph, GROUP_TYPE);
+}
+
+static const char *pinctrl_scmi_get_group_name(struct pinctrl_dev *pctldev, unsigned int selector)
+{
+	int ret;
+	const char *name;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	ret = pinctrl_ops->name_get(pmx->ph, selector, GROUP_TYPE, &name);
+	if (ret) {
+		dev_err(pmx->dev, "get name failed with err %d", ret);
+		return NULL;
+	}
+
+	return name;
+}
+
+static int pinctrl_scmi_get_group_pins(struct pinctrl_dev *pctldev,
+				       unsigned int selector,
+				       const unsigned int **pins,
+				       unsigned int *num_pins)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->group_pins_get(pmx->ph, selector, pins, num_pins);
+}
+
+static const struct pinctrl_ops pinctrl_scmi_pinctrl_ops = {
+	.get_groups_count = pinctrl_scmi_get_groups_count,
+	.get_group_name = pinctrl_scmi_get_group_name,
+	.get_group_pins = pinctrl_scmi_get_group_pins,
+#ifdef CONFIG_OF
+	.dt_node_to_map = pinconf_generic_dt_node_to_map_all,
+	.dt_free_map = pinconf_generic_dt_free_map,
+#endif
+};
+
+static int pinctrl_scmi_get_functions_count(struct pinctrl_dev *pctldev)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->count_get(pmx->ph, FUNCTION_TYPE);
+}
+
+static const char *pinctrl_scmi_get_function_name(struct pinctrl_dev *pctldev,
+						  unsigned int selector)
+{
+	int ret;
+	const char *name;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	ret = pinctrl_ops->name_get(pmx->ph, selector, FUNCTION_TYPE, &name);
+	if (ret) {
+		dev_err(pmx->dev, "get name failed with err %d", ret);
+		return NULL;
+	}
+
+	return name;
+}
+
+static int pinctrl_scmi_get_function_groups(struct pinctrl_dev *pctldev,
+					    unsigned int selector,
+					    const char * const **groups,
+					    unsigned int * const num_groups)
+{
+	const unsigned int *group_ids;
+	int ret, i;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	if (!groups || !num_groups)
+		return -EINVAL;
+
+	if (selector < pmx->nr_functions &&
+	    pmx->functions[selector].num_groups) {
+		*groups = (const char * const *)pmx->functions[selector].groups;
+		*num_groups = pmx->functions[selector].num_groups;
+		return 0;
+	}
+
+	ret = pinctrl_ops->function_groups_get(pmx->ph, selector,
+					       &pmx->functions[selector].num_groups,
+					       &group_ids);
+	if (ret) {
+		dev_err(pmx->dev, "Unable to get function groups, err %d", ret);
+		return ret;
+	}
+
+	*num_groups = pmx->functions[selector].num_groups;
+	if (!*num_groups)
+		return -EINVAL;
+
+	pmx->functions[selector].groups =
+		devm_kcalloc(pmx->dev, *num_groups, sizeof(*pmx->functions[selector].groups),
+			     GFP_KERNEL);
+	if (!pmx->functions[selector].groups)
+		return -ENOMEM;
+
+	for (i = 0; i < *num_groups; i++) {
+		pmx->functions[selector].groups[i] =
+			pinctrl_scmi_get_group_name(pmx->pctldev,
+						    group_ids[i]);
+		if (!pmx->functions[selector].groups[i]) {
+			ret = -ENOMEM;
+			goto err_free;
+		}
+	}
+
+	*groups = (const char * const *)pmx->functions[selector].groups;
+
+	return 0;
+
+err_free:
+	devm_kfree(pmx->dev, pmx->functions[selector].groups);
+
+	return ret;
+}
+
+static int pinctrl_scmi_func_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
+				     unsigned int group)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->mux_set(pmx->ph, selector, group);
+}
+
+static int pinctrl_scmi_request(struct pinctrl_dev *pctldev, unsigned int offset)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->pin_request(pmx->ph, offset);
+}
+
+static int pinctrl_scmi_free(struct pinctrl_dev *pctldev, unsigned int offset)
+{
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	return pinctrl_ops->pin_free(pmx->ph, offset);
+}
+
+static const struct pinmux_ops pinctrl_scmi_pinmux_ops = {
+	.request = pinctrl_scmi_request,
+	.free = pinctrl_scmi_free,
+	.get_functions_count = pinctrl_scmi_get_functions_count,
+	.get_function_name = pinctrl_scmi_get_function_name,
+	.get_function_groups = pinctrl_scmi_get_function_groups,
+	.set_mux = pinctrl_scmi_func_set_mux,
+};
+
+static int pinctrl_scmi_pinconf_get(struct pinctrl_dev *pctldev, unsigned int _pin,
+				    unsigned long *config)
+{
+	int ret;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+	enum pin_config_param config_type;
+	unsigned long config_value;
+
+	if (!config)
+		return -EINVAL;
+
+	config_type = pinconf_to_config_param(*config);
+
+	ret = pinctrl_ops->config_get(pmx->ph, _pin, PIN_TYPE, config_type, &config_value);
+	if (ret)
+		return ret;
+
+	*config = pinconf_to_config_packed(config_type, config_value);
+
+	return 0;
+}
+
+static int pinctrl_scmi_pinconf_set(struct pinctrl_dev *pctldev,
+				    unsigned int _pin,
+				    unsigned long *configs,
+				    unsigned int num_configs)
+{
+	int ret;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+	if (!configs || !num_configs)
+		return -EINVAL;
+
+	ret = pinctrl_ops->config_set(pmx->ph, _pin, PIN_TYPE, configs, num_configs);
+	if (ret)
+		dev_err(pmx->dev, "Error parsing config %d\n", ret);
+
+	return ret;
+}
+
+static int pinctrl_scmi_pinconf_group_set(struct pinctrl_dev *pctldev,
+					  unsigned int group,
+					  unsigned long *configs,
+					  unsigned int num_configs)
+{
+	int ret;
+	struct scmi_pinctrl *pmx =  pinctrl_dev_get_drvdata(pctldev);
+
+	if (!configs || !num_configs)
+		return -EINVAL;
+
+	ret = pinctrl_ops->config_set(pmx->ph, group, GROUP_TYPE, configs, num_configs);
+	if (ret)
+		dev_err(pmx->dev, "Error parsing config %d", ret);
+
+	return ret;
+};
+
+static int pinctrl_scmi_pinconf_group_get(struct pinctrl_dev *pctldev,
+					  unsigned int group,
+					  unsigned long *config)
+{
+	int ret;
+	struct scmi_pinctrl *pmx = pinctrl_dev_get_drvdata(pctldev);
+	enum pin_config_param config_type;
+	unsigned long config_value;
+
+	if (!config)
+		return -EINVAL;
+
+	config_type = pinconf_to_config_param(*config);
+
+	ret = pinctrl_ops->config_get(pmx->ph, group, GROUP_TYPE, config_type, &config_value);
+	if (ret)
+		return ret;
+
+	*config = pinconf_to_config_packed(config_type, config_value);
+
+	return 0;
+}
+
+static const struct pinconf_ops pinctrl_scmi_pinconf_ops = {
+	.is_generic = true,
+	.pin_config_get = pinctrl_scmi_pinconf_get,
+	.pin_config_set = pinctrl_scmi_pinconf_set,
+	.pin_config_group_set = pinctrl_scmi_pinconf_group_set,
+	.pin_config_group_get = pinctrl_scmi_pinconf_group_get,
+	.pin_config_config_dbg_show = pinconf_generic_dump_config,
+};
+
+static int pinctrl_scmi_get_pins(struct scmi_pinctrl *pmx,
+				 unsigned int *nr_pins,
+				 const struct pinctrl_pin_desc **pins)
+{
+	int ret, i;
+
+	if (!pins || !nr_pins)
+		return -EINVAL;
+
+	if (pmx->nr_pins) {
+		*pins = pmx->pins;
+		*nr_pins = pmx->nr_pins;
+		return 0;
+	}
+
+	*nr_pins = pinctrl_ops->count_get(pmx->ph, PIN_TYPE);
+
+	pmx->nr_pins = *nr_pins;
+	pmx->pins = devm_kmalloc_array(pmx->dev, *nr_pins, sizeof(*pmx->pins), GFP_KERNEL);
+	if (!pmx->pins)
+		return -ENOMEM;
+
+	for (i = 0; i < *nr_pins; i++) {
+		pmx->pins[i].number = i;
+		ret = pinctrl_ops->name_get(pmx->ph, i, PIN_TYPE, &pmx->pins[i].name);
+		if (ret) {
+			dev_err(pmx->dev, "Can't get name for pin %d: rc %d", i, ret);
+			pmx->nr_pins = 0;
+			return ret;
+		}
+	}
+
+	*pins = pmx->pins;
+	dev_dbg(pmx->dev, "got pins %d", *nr_pins);
+
+	return 0;
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+	{ SCMI_PROTOCOL_PINCTRL, "pinctrl" },
+	{ }
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static int scmi_pinctrl_probe(struct scmi_device *sdev)
+{
+	int ret;
+	struct device *dev = &sdev->dev;
+	struct scmi_pinctrl *pmx;
+	const struct scmi_handle *handle;
+	struct scmi_protocol_handle *ph;
+
+	if (!sdev || !sdev->handle)
+		return -EINVAL;
+
+	handle = sdev->handle;
+
+	pinctrl_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_PINCTRL, &ph);
+	if (IS_ERR(pinctrl_ops))
+		return PTR_ERR(pinctrl_ops);
+
+	pmx = devm_kzalloc(dev, sizeof(*pmx), GFP_KERNEL);
+	if (!pmx)
+		return -ENOMEM;
+
+	pmx->ph = ph;
+
+	pmx->dev = dev;
+	pmx->pctl_desc.name = DRV_NAME;
+	pmx->pctl_desc.owner = THIS_MODULE;
+	pmx->pctl_desc.pctlops = &pinctrl_scmi_pinctrl_ops;
+	pmx->pctl_desc.pmxops = &pinctrl_scmi_pinmux_ops;
+	pmx->pctl_desc.confops = &pinctrl_scmi_pinconf_ops;
+
+	ret = pinctrl_scmi_get_pins(pmx, &pmx->pctl_desc.npins,
+				    &pmx->pctl_desc.pins);
+	if (ret)
+		return ret;
+
+	ret = devm_pinctrl_register_and_init(dev, &pmx->pctl_desc, pmx, &pmx->pctldev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to register pinctrl\n");
+
+	pmx->nr_functions = pinctrl_scmi_get_functions_count(pmx->pctldev);
+	pmx->nr_groups = pinctrl_scmi_get_groups_count(pmx->pctldev);
+
+	if (pmx->nr_functions) {
+		pmx->functions =
+			devm_kcalloc(dev, pmx->nr_functions, sizeof(*pmx->functions),
+				     GFP_KERNEL);
+		if (!pmx->functions)
+			return -ENOMEM;
+	}
+
+	if (pmx->nr_groups) {
+		pmx->groups =
+			devm_kcalloc(dev, pmx->nr_groups, sizeof(*pmx->groups), GFP_KERNEL);
+		if (!pmx->groups)
+			return -ENOMEM;
+	}
+
+	return pinctrl_enable(pmx->pctldev);
+}
+
+static struct scmi_driver scmi_pinctrl_driver = {
+	.name = DRV_NAME,
+	.probe = scmi_pinctrl_probe,
+	.id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_pinctrl_driver);
+
+MODULE_AUTHOR("Oleksii Moisieiev <oleksii_moisieiev@epam.com>");
+MODULE_DESCRIPTION("ARM SCMI pin controller driver");
+MODULE_LICENSE("GPL");