diff mbox series

[2/2] clk: rs9: Add Renesas 9-series PCIe clock generator driver

Message ID 20220213173310.152230-2-marex@denx.de
State Superseded
Headers show
Series None | expand

Commit Message

Marek Vasut Feb. 13, 2022, 5:33 p.m. UTC
Add driver for Renesas 9-series PCIe clock generators. This driver
is designed to support 9FGV/9DBV/9DMV/9FGL/9DML/9QXL/9SQ series I2C
PCIe clock generators, currently the only tested and supported chip
is 9FGV0241.

The driver is capable of configuring per-chip spread spectrum mode
and output amplitude, as well as per-output slew rate.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: devicetree@vger.kernel.org
To: linux-clk@vger.kernel.org
---
 drivers/clk/Kconfig            |   9 +
 drivers/clk/Makefile           |   1 +
 drivers/clk/clk-renesas-pcie.c | 336 +++++++++++++++++++++++++++++++++
 3 files changed, 346 insertions(+)
 create mode 100644 drivers/clk/clk-renesas-pcie.c

Comments

Stephen Boyd Feb. 17, 2022, 11:45 p.m. UTC | #1
Quoting Marek Vasut (2022-02-13 09:33:10)
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 6a98291350b64..3ec27842ec779 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -68,6 +68,7 @@ obj-$(CONFIG_COMMON_CLK_STM32MP157)   += clk-stm32mp1.o
>  obj-$(CONFIG_COMMON_CLK_TPS68470)      += clk-tps68470.o
>  obj-$(CONFIG_CLK_TWL6040)              += clk-twl6040.o
>  obj-$(CONFIG_ARCH_VT8500)              += clk-vt8500.o
> +obj-$(CONFIG_COMMON_CLK_RS9_PCIE)      += clk-renesas-pcie.o

Is there a reason it doesn't go into drivers/clk/renesas?

>  obj-$(CONFIG_COMMON_CLK_VC5)           += clk-versaclock5.o
>  obj-$(CONFIG_COMMON_CLK_WM831X)                += clk-wm831x.o
>  obj-$(CONFIG_COMMON_CLK_XGENE)         += clk-xgene.o
> diff --git a/drivers/clk/clk-renesas-pcie.c b/drivers/clk/clk-renesas-pcie.c
> new file mode 100644
> index 0000000000000..0ad132cbe41b8
> --- /dev/null
> +++ b/drivers/clk/clk-renesas-pcie.c
> @@ -0,0 +1,336 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Driver for Renesas 9-series PCIe clock generator driver
> + *
> + * The following series can be supported:
> + *   - 9FGV/9DBV/9DMV/9FGL/9DML/9QXL/9SQ
> + * Currently supported:
> + *   - 9FGV0241
> + *
> + * Copyright (C) 2022 Marek Vasut <marex@denx.de>
> + */
> +
> +#include <linux/clk.h>

Drop this include please.

> +#include <linux/clk-provider.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>

Is this used? If not please remove.

> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>

Is this used? If not please remove.

> +#include <linux/rational.h>

Is this used? If not please remove.

> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +
> +#define RS9_REG_OE                             0x0
> +#define RS9_REG_OE_DIF_OE(n)                   BIT((n) + 1)
> +#define RS9_REG_SS                             0x1
> +#define RS9_REG_SS_AMP_0V6                     0x0
> +#define RS9_REG_SS_AMP_0V7                     0x1
> +#define RS9_REG_SS_AMP_0V8                     0x2
> +#define RS9_REG_SS_AMP_0V9                     0x3
> +#define RS9_REG_SS_AMP_MASK                    0x3
> +#define RS9_REG_SS_SSC_100                     0
> +#define RS9_REG_SS_SSC_M025                    (1 << 3)
> +#define RS9_REG_SS_SSC_M050                    (3 << 3)
> +#define RS9_REG_SS_SSC_MASK                    (3 << 3)
> +#define RS9_REG_SS_SSC_LOCK                    BIT(5)
> +#define RS9_REG_SR                             0x2
> +#define RS9_REG_SR_2V0_DIF(n)                  0
> +#define RS9_REG_SR_3V0_DIF(n)                  BIT((n) + 1)
> +#define RS9_REG_SR_DIF_MASK(n)         BIT((n) + 1)
> +#define RS9_REG_REF                            0x3
> +#define RS9_REG_REF_OE                         BIT(4)
> +#define RS9_REG_REF_OD                         BIT(5)
> +#define RS9_REG_REF_SR_SLOWEST                 0
> +#define RS9_REG_REF_SR_SLOW                    (1 << 6)
> +#define RS9_REG_REF_SR_FAST                    (2 << 6)
> +#define RS9_REG_REF_SR_FASTER                  (3 << 6)
> +#define RS9_REG_VID                            0x5
> +#define RS9_REG_DID                            0x6
> +#define RS9_REG_BCP                            0x7
> +
> +/* Supported Renesas 9-series models. */
> +enum rs9_model {
> +       RENESAS_9FGV0241,
> +};
> +
> +/* Structure to describe features of a particular 9-series model */
> +struct rs9_chip_info {
> +       const enum rs9_model    model;
> +       unsigned int            num_clks;
> +};
> +
> +struct rs9_driver_data {
> +       struct i2c_client       *client;
> +       struct regmap           *regmap;
> +       const struct rs9_chip_info *chip_info;
> +       struct clk              *pin_xin;
> +       struct clk_hw           *clk_dif[2];
> +       u8                      pll_amplitude;
> +       u8                      pll_ssc;
> +       u8                      clk_dif_sr;
> +};
> +
> +/*
> + * Renesas 9-series i2c regmap
> + */
> +static const struct regmap_range rs9_readable_ranges[] = {
> +       regmap_reg_range(RS9_REG_OE, RS9_REG_REF),
> +       regmap_reg_range(RS9_REG_VID, RS9_REG_BCP),
> +};
> +
> +static const struct regmap_access_table rs9_readable_table = {
> +       .yes_ranges = rs9_readable_ranges,
> +       .n_yes_ranges = ARRAY_SIZE(rs9_readable_ranges),
> +};
> +
> +static const struct regmap_range rs9_writeable_ranges[] = {
> +       regmap_reg_range(RS9_REG_OE, RS9_REG_REF),
> +       regmap_reg_range(RS9_REG_BCP, RS9_REG_BCP),
> +};
> +
> +static const struct regmap_access_table rs9_writeable_table = {
> +       .yes_ranges = rs9_writeable_ranges,
> +       .n_yes_ranges = ARRAY_SIZE(rs9_writeable_ranges),
> +};
> +
> +static const struct regmap_config rs9_regmap_config = {
> +       .reg_bits = 8,
> +       .val_bits = 8,
> +       .cache_type = REGCACHE_RBTREE,
> +       .max_register = 0x8,

That's a huge cache!

> +       .rd_table = &rs9_readable_table,
> +       .wr_table = &rs9_writeable_table,
> +};
> +
> +static int rs9_get_output_config(struct rs9_driver_data *rs9, int idx)
> +{
> +       struct i2c_client *client = rs9->client;
> +       unsigned char *name = "DIF0";
> +       struct device_node *np;
> +       int ret;
> +       u32 sr;
> +
> +       /* Set defaults */
> +       rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
> +       rs9->clk_dif_sr |= RS9_REG_SR_3V0_DIF(idx);
> +
> +       name[3] += idx;
> +       np = of_get_child_by_name(client->dev.of_node, name);
> +       if (!np)
> +               return 0;
> +
> +       /* Output clock slew rate */
> +       ret = of_property_read_u32(np, "renesas,slew-rate", &sr);

Put of_node_put(np) here please

> +       if (!ret) {
> +               if (sr == 2000000) {            /* 2V/ns */
> +                       rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
> +                       rs9->clk_dif_sr |= RS9_REG_SR_2V0_DIF(idx);
> +               } else if (sr == 3000000) {     /* 3V/ns (default) */
> +                       rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
> +                       rs9->clk_dif_sr |= RS9_REG_SR_3V0_DIF(idx);
> +               } else
> +                       ret = dev_err_probe(&client->dev, -EINVAL,
> +                                           "Invalid renesas,slew-rate value\n");
> +       }
> +
> +       of_node_put(np);
> +
> +       return ret;
> +}
> +
> +static int rs9_get_common_config(struct rs9_driver_data *rs9)
> +{
> +       struct i2c_client *client = rs9->client;
> +       struct device_node *np = client->dev.of_node;
> +       unsigned int amp, ssc;
> +       int ret;
> +
> +       /* Set defaults */
> +       rs9->pll_amplitude = RS9_REG_SS_AMP_0V7;
> +       rs9->pll_ssc = RS9_REG_SS_SSC_100;
> +
> +       /* Output clock amplitude */
> +       ret = of_property_read_u32(np, "renesas,out-amplitude", &amp);
> +       if (!ret) {
> +               if (amp == 600000)      /* 0.6V */
> +                       rs9->pll_amplitude = RS9_REG_SS_AMP_0V6;
> +               else if (amp == 700000) /* 0.7V (default) */
> +                       rs9->pll_amplitude = RS9_REG_SS_AMP_0V7;
> +               else if (amp == 800000) /* 0.8V */
> +                       rs9->pll_amplitude = RS9_REG_SS_AMP_0V8;
> +               else if (amp == 900000) /* 0.9V */
> +                       rs9->pll_amplitude = RS9_REG_SS_AMP_0V9;
> +               else
> +                       return dev_err_probe(&client->dev, -EINVAL,
> +                                            "Invalid renesas,out-amplitude value\n");
> +       }
> +
> +       /* Output clock spread spectrum */
> +       ret = of_property_read_u32(np, "renesas,out-spread-spectrum", &ssc);
> +       if (!ret) {
> +               if (ssc == 100000)      /* 100% ... no spread (default) */
> +                       rs9->pll_ssc = RS9_REG_SS_SSC_100;
> +               else if (ssc == 99750)  /* -0.25% ... down spread */
> +                       rs9->pll_ssc = RS9_REG_SS_SSC_M025;
> +               else if (ssc == 99500)  /* -0.50% ... down spread */
> +                       rs9->pll_ssc = RS9_REG_SS_SSC_M050;
> +               else
> +                       return dev_err_probe(&client->dev, -EINVAL,
> +                                            "Invalid renesas,out-spread-spectrum value\n");
> +       }
> +
> +       return 0;
> +}
> +
> +static void rs9_update_config(struct rs9_driver_data *rs9)
> +{
> +       int i;
> +
> +       /* If amplitude is non-default, update it. */
> +       if (rs9->pll_amplitude != RS9_REG_SS_AMP_0V7) {
> +               regmap_update_bits(rs9->regmap, RS9_REG_SS, RS9_REG_SS_AMP_MASK,
> +                                  rs9->pll_amplitude);
> +       }
> +
> +       /* If SSC is non-default, update it. */
> +       if (rs9->pll_ssc != RS9_REG_SS_SSC_100) {
> +               regmap_update_bits(rs9->regmap, RS9_REG_SS, RS9_REG_SS_SSC_MASK,
> +                                  rs9->pll_ssc);
> +       }
> +
> +       for (i = 0; i < rs9->chip_info->num_clks; i++) {
> +               if (rs9->clk_dif_sr & RS9_REG_SR_3V0_DIF(i))
> +                       continue;
> +
> +               regmap_update_bits(rs9->regmap, RS9_REG_SR, RS9_REG_SR_3V0_DIF(i),
> +                                  rs9->clk_dif_sr & RS9_REG_SR_3V0_DIF(i));
> +       }
> +}
> +
> +static struct clk_hw *
> +rs9_of_clk_get(struct of_phandle_args *clkspec, void *data)
> +{
> +       struct rs9_driver_data *rs9 = data;
> +       unsigned int idx = clkspec->args[0];
> +
> +       return rs9->clk_dif[idx];
> +}
> +
> +static const struct of_device_id clk_rs9_of_match[];

Why the forward declare?

> +
> +static int rs9_probe(struct i2c_client *client, const struct i2c_device_id *id)
> +{
> +       struct device_node *np = client->dev.of_node;
> +       unsigned char *name = "DIF0";
> +       struct rs9_driver_data *rs9;
> +       const char *parent_clk;
> +       struct clk_hw *hw;
> +       int i, ret;
> +
> +       rs9 = devm_kzalloc(&client->dev, sizeof(*rs9), GFP_KERNEL);
> +       if (!rs9)
> +               return -ENOMEM;
> +
> +       i2c_set_clientdata(client, rs9);
> +       rs9->client = client;
> +       rs9->chip_info = of_device_get_match_data(&client->dev);

Check for NULL? Use device_get_match_data()? Or does that not work for
i2c devices?

> +
> +       /* Fetch common configuration from DT (if specified) */
> +       ret = rs9_get_common_config(rs9);
> +       if (ret)
> +               return ret;
> +
> +       /* Fetch DIFx output configuration from DT (if specified) */
> +       for (i = 0; i < rs9->chip_info->num_clks; i++) {
> +               ret = rs9_get_output_config(rs9, i);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       /* Mandatory XTal */

Oh it's mandatory here but not in the binding?

> +       parent_clk = of_clk_get_parent_name(np, 0);

Use clk_parent_data please.

> +       if (!parent_clk)
> +               return dev_err_probe(&client->dev, -EINVAL,
> +                                    "Missing XTal input clock\n");
> +
> +       rs9->regmap = devm_regmap_init_i2c(client, &rs9_regmap_config);
> +       if (IS_ERR(rs9->regmap))
> +               return dev_err_probe(&client->dev, PTR_ERR(rs9->regmap),
> +                                    "Failed to allocate register map\n");
> +
> +       /* Register clock */
> +       for (i = 0; i < rs9->chip_info->num_clks; i++) {
> +               name[3]++;
> +               hw = clk_hw_register_fixed_factor(&client->dev, name,
> +                                                 parent_clk, 0, 4, 1);
> +               if (IS_ERR(hw))
> +                       return PTR_ERR(hw);
> +
> +               rs9->clk_dif[i] = hw;
> +       }
> +
> +       ret = devm_of_clk_add_hw_provider(&client->dev, rs9_of_clk_get, rs9);
> +       if (!ret)
> +               rs9_update_config(rs9);
> +
> +       return ret;
> +}
Marek Vasut Feb. 18, 2022, 1:26 a.m. UTC | #2
On 2/18/22 00:45, Stephen Boyd wrote:
> Quoting Marek Vasut (2022-02-13 09:33:10)
>> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
>> index 6a98291350b64..3ec27842ec779 100644
>> --- a/drivers/clk/Makefile
>> +++ b/drivers/clk/Makefile
>> @@ -68,6 +68,7 @@ obj-$(CONFIG_COMMON_CLK_STM32MP157)   += clk-stm32mp1.o
>>   obj-$(CONFIG_COMMON_CLK_TPS68470)      += clk-tps68470.o
>>   obj-$(CONFIG_CLK_TWL6040)              += clk-twl6040.o
>>   obj-$(CONFIG_ARCH_VT8500)              += clk-vt8500.o
>> +obj-$(CONFIG_COMMON_CLK_RS9_PCIE)      += clk-renesas-pcie.o
> 
> Is there a reason it doesn't go into drivers/clk/renesas?

The drivers/clk/renesas/ is for renesas SoC (R-Car/RZ/...),
this chip is different group (it's probably even IDT PLL IP).

[...]

>> +#include <linux/mod_devicetable.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_platform.h>
> 
> Is this used? If not please remove.

This one is for of_device_get_match_data()

[...]

>> +static struct clk_hw *
>> +rs9_of_clk_get(struct of_phandle_args *clkspec, void *data)
>> +{
>> +       struct rs9_driver_data *rs9 = data;
>> +       unsigned int idx = clkspec->args[0];
>> +
>> +       return rs9->clk_dif[idx];
>> +}
>> +
>> +static const struct of_device_id clk_rs9_of_match[];
> 
> Why the forward declare?

Remnant from development, dropped.

>> +static int rs9_probe(struct i2c_client *client, const struct i2c_device_id *id)
>> +{
>> +       struct device_node *np = client->dev.of_node;
>> +       unsigned char *name = "DIF0";
>> +       struct rs9_driver_data *rs9;
>> +       const char *parent_clk;
>> +       struct clk_hw *hw;
>> +       int i, ret;
>> +
>> +       rs9 = devm_kzalloc(&client->dev, sizeof(*rs9), GFP_KERNEL);
>> +       if (!rs9)
>> +               return -ENOMEM;
>> +
>> +       i2c_set_clientdata(client, rs9);
>> +       rs9->client = client;
>> +       rs9->chip_info = of_device_get_match_data(&client->dev);
> 
> Check for NULL? Use device_get_match_data()? Or does that not work for
> i2c devices?
> 
>> +
>> +       /* Fetch common configuration from DT (if specified) */
>> +       ret = rs9_get_common_config(rs9);
>> +       if (ret)
>> +               return ret;
>> +
>> +       /* Fetch DIFx output configuration from DT (if specified) */
>> +       for (i = 0; i < rs9->chip_info->num_clks; i++) {
>> +               ret = rs9_get_output_config(rs9, i);
>> +               if (ret)
>> +                       return ret;
>> +       }
>> +
>> +       /* Mandatory XTal */
> 
> Oh it's mandatory here but not in the binding?
> 
>> +       parent_clk = of_clk_get_parent_name(np, 0);
> 
> Use clk_parent_data please.

This one line I don't understand -- can you expand on what you expect me 
to do here ?

>> +       if (!parent_clk)
>> +               return dev_err_probe(&client->dev, -EINVAL,
>> +                                    "Missing XTal input clock\n");
>> +
>> +       rs9->regmap = devm_regmap_init_i2c(client, &rs9_regmap_config);
>> +       if (IS_ERR(rs9->regmap))
>> +               return dev_err_probe(&client->dev, PTR_ERR(rs9->regmap),
>> +                                    "Failed to allocate register map\n");
>> +
>> +       /* Register clock */
>> +       for (i = 0; i < rs9->chip_info->num_clks; i++) {
>> +               name[3]++;
>> +               hw = clk_hw_register_fixed_factor(&client->dev, name,
>> +                                                 parent_clk, 0, 4, 1);
>> +               if (IS_ERR(hw))
>> +                       return PTR_ERR(hw);
>> +
>> +               rs9->clk_dif[i] = hw;
>> +       }
>> +
>> +       ret = devm_of_clk_add_hw_provider(&client->dev, rs9_of_clk_get, rs9);
>> +       if (!ret)
>> +               rs9_update_config(rs9);
>> +
>> +       return ret;
>> +}

[...]
diff mbox series

Patch

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 3cdf33470a750..05fc6fb2fddd5 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -340,6 +340,15 @@  config COMMON_CLK_OXNAS
 	help
 	  Support for the OXNAS SoC Family clocks.
 
+config COMMON_CLK_RS9_PCIE
+	tristate "Clock driver for Renesas 9-series PCIe clock generators"
+	depends on I2C
+	depends on OF
+	select REGMAP_I2C
+	help
+	  This driver supports the Renesas 9-series PCIe clock generator
+	  models 9FGV/9DBV/9DMV/9FGL/9DML/9QXL/9SQ.
+
 config COMMON_CLK_VC5
 	tristate "Clock driver for IDT VersaClock 5,6 devices"
 	depends on I2C
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 6a98291350b64..3ec27842ec779 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -68,6 +68,7 @@  obj-$(CONFIG_COMMON_CLK_STM32MP157)	+= clk-stm32mp1.o
 obj-$(CONFIG_COMMON_CLK_TPS68470)      += clk-tps68470.o
 obj-$(CONFIG_CLK_TWL6040)		+= clk-twl6040.o
 obj-$(CONFIG_ARCH_VT8500)		+= clk-vt8500.o
+obj-$(CONFIG_COMMON_CLK_RS9_PCIE)	+= clk-renesas-pcie.o
 obj-$(CONFIG_COMMON_CLK_VC5)		+= clk-versaclock5.o
 obj-$(CONFIG_COMMON_CLK_WM831X)		+= clk-wm831x.o
 obj-$(CONFIG_COMMON_CLK_XGENE)		+= clk-xgene.o
diff --git a/drivers/clk/clk-renesas-pcie.c b/drivers/clk/clk-renesas-pcie.c
new file mode 100644
index 0000000000000..0ad132cbe41b8
--- /dev/null
+++ b/drivers/clk/clk-renesas-pcie.c
@@ -0,0 +1,336 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for Renesas 9-series PCIe clock generator driver
+ *
+ * The following series can be supported:
+ *   - 9FGV/9DBV/9DMV/9FGL/9DML/9QXL/9SQ
+ * Currently supported:
+ *   - 9FGV0241
+ *
+ * Copyright (C) 2022 Marek Vasut <marex@denx.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/rational.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#define RS9_REG_OE				0x0
+#define RS9_REG_OE_DIF_OE(n)			BIT((n) + 1)
+#define RS9_REG_SS				0x1
+#define RS9_REG_SS_AMP_0V6			0x0
+#define RS9_REG_SS_AMP_0V7			0x1
+#define RS9_REG_SS_AMP_0V8			0x2
+#define RS9_REG_SS_AMP_0V9			0x3
+#define RS9_REG_SS_AMP_MASK			0x3
+#define RS9_REG_SS_SSC_100			0
+#define RS9_REG_SS_SSC_M025			(1 << 3)
+#define RS9_REG_SS_SSC_M050			(3 << 3)
+#define RS9_REG_SS_SSC_MASK			(3 << 3)
+#define RS9_REG_SS_SSC_LOCK			BIT(5)
+#define RS9_REG_SR				0x2
+#define RS9_REG_SR_2V0_DIF(n)			0
+#define RS9_REG_SR_3V0_DIF(n)			BIT((n) + 1)
+#define RS9_REG_SR_DIF_MASK(n)		BIT((n) + 1)
+#define RS9_REG_REF				0x3
+#define RS9_REG_REF_OE				BIT(4)
+#define RS9_REG_REF_OD				BIT(5)
+#define RS9_REG_REF_SR_SLOWEST			0
+#define RS9_REG_REF_SR_SLOW			(1 << 6)
+#define RS9_REG_REF_SR_FAST			(2 << 6)
+#define RS9_REG_REF_SR_FASTER			(3 << 6)
+#define RS9_REG_VID				0x5
+#define RS9_REG_DID				0x6
+#define RS9_REG_BCP				0x7
+
+/* Supported Renesas 9-series models. */
+enum rs9_model {
+	RENESAS_9FGV0241,
+};
+
+/* Structure to describe features of a particular 9-series model */
+struct rs9_chip_info {
+	const enum rs9_model	model;
+	unsigned int		num_clks;
+};
+
+struct rs9_driver_data {
+	struct i2c_client	*client;
+	struct regmap		*regmap;
+	const struct rs9_chip_info *chip_info;
+	struct clk		*pin_xin;
+	struct clk_hw		*clk_dif[2];
+	u8			pll_amplitude;
+	u8			pll_ssc;
+	u8			clk_dif_sr;
+};
+
+/*
+ * Renesas 9-series i2c regmap
+ */
+static const struct regmap_range rs9_readable_ranges[] = {
+	regmap_reg_range(RS9_REG_OE, RS9_REG_REF),
+	regmap_reg_range(RS9_REG_VID, RS9_REG_BCP),
+};
+
+static const struct regmap_access_table rs9_readable_table = {
+	.yes_ranges = rs9_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(rs9_readable_ranges),
+};
+
+static const struct regmap_range rs9_writeable_ranges[] = {
+	regmap_reg_range(RS9_REG_OE, RS9_REG_REF),
+	regmap_reg_range(RS9_REG_BCP, RS9_REG_BCP),
+};
+
+static const struct regmap_access_table rs9_writeable_table = {
+	.yes_ranges = rs9_writeable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(rs9_writeable_ranges),
+};
+
+static const struct regmap_config rs9_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.cache_type = REGCACHE_RBTREE,
+	.max_register = 0x8,
+	.rd_table = &rs9_readable_table,
+	.wr_table = &rs9_writeable_table,
+};
+
+static int rs9_get_output_config(struct rs9_driver_data *rs9, int idx)
+{
+	struct i2c_client *client = rs9->client;
+	unsigned char *name = "DIF0";
+	struct device_node *np;
+	int ret;
+	u32 sr;
+
+	/* Set defaults */
+	rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
+	rs9->clk_dif_sr |= RS9_REG_SR_3V0_DIF(idx);
+
+	name[3] += idx;
+	np = of_get_child_by_name(client->dev.of_node, name);
+	if (!np)
+		return 0;
+
+	/* Output clock slew rate */
+	ret = of_property_read_u32(np, "renesas,slew-rate", &sr);
+	if (!ret) {
+		if (sr == 2000000) {		/* 2V/ns */
+			rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
+			rs9->clk_dif_sr |= RS9_REG_SR_2V0_DIF(idx);
+		} else if (sr == 3000000) {	/* 3V/ns (default) */
+			rs9->clk_dif_sr &= ~RS9_REG_SR_DIF_MASK(idx);
+			rs9->clk_dif_sr |= RS9_REG_SR_3V0_DIF(idx);
+		} else
+			ret = dev_err_probe(&client->dev, -EINVAL,
+					    "Invalid renesas,slew-rate value\n");
+	}
+
+	of_node_put(np);
+
+	return ret;
+}
+
+static int rs9_get_common_config(struct rs9_driver_data *rs9)
+{
+	struct i2c_client *client = rs9->client;
+	struct device_node *np = client->dev.of_node;
+	unsigned int amp, ssc;
+	int ret;
+
+	/* Set defaults */
+	rs9->pll_amplitude = RS9_REG_SS_AMP_0V7;
+	rs9->pll_ssc = RS9_REG_SS_SSC_100;
+
+	/* Output clock amplitude */
+	ret = of_property_read_u32(np, "renesas,out-amplitude", &amp);
+	if (!ret) {
+		if (amp == 600000)	/* 0.6V */
+			rs9->pll_amplitude = RS9_REG_SS_AMP_0V6;
+		else if (amp == 700000)	/* 0.7V (default) */
+			rs9->pll_amplitude = RS9_REG_SS_AMP_0V7;
+		else if (amp == 800000)	/* 0.8V */
+			rs9->pll_amplitude = RS9_REG_SS_AMP_0V8;
+		else if (amp == 900000)	/* 0.9V */
+			rs9->pll_amplitude = RS9_REG_SS_AMP_0V9;
+		else
+			return dev_err_probe(&client->dev, -EINVAL,
+					     "Invalid renesas,out-amplitude value\n");
+	}
+
+	/* Output clock spread spectrum */
+	ret = of_property_read_u32(np, "renesas,out-spread-spectrum", &ssc);
+	if (!ret) {
+		if (ssc == 100000)	/* 100% ... no spread (default) */
+			rs9->pll_ssc = RS9_REG_SS_SSC_100;
+		else if (ssc == 99750)	/* -0.25% ... down spread */
+			rs9->pll_ssc = RS9_REG_SS_SSC_M025;
+		else if (ssc == 99500)	/* -0.50% ... down spread */
+			rs9->pll_ssc = RS9_REG_SS_SSC_M050;
+		else
+			return dev_err_probe(&client->dev, -EINVAL,
+					     "Invalid renesas,out-spread-spectrum value\n");
+	}
+
+	return 0;
+}
+
+static void rs9_update_config(struct rs9_driver_data *rs9)
+{
+	int i;
+
+	/* If amplitude is non-default, update it. */
+	if (rs9->pll_amplitude != RS9_REG_SS_AMP_0V7) {
+		regmap_update_bits(rs9->regmap, RS9_REG_SS, RS9_REG_SS_AMP_MASK,
+				   rs9->pll_amplitude);
+	}
+
+	/* If SSC is non-default, update it. */
+	if (rs9->pll_ssc != RS9_REG_SS_SSC_100) {
+		regmap_update_bits(rs9->regmap, RS9_REG_SS, RS9_REG_SS_SSC_MASK,
+				   rs9->pll_ssc);
+	}
+
+	for (i = 0; i < rs9->chip_info->num_clks; i++) {
+		if (rs9->clk_dif_sr & RS9_REG_SR_3V0_DIF(i))
+			continue;
+
+		regmap_update_bits(rs9->regmap, RS9_REG_SR, RS9_REG_SR_3V0_DIF(i),
+				   rs9->clk_dif_sr & RS9_REG_SR_3V0_DIF(i));
+	}
+}
+
+static struct clk_hw *
+rs9_of_clk_get(struct of_phandle_args *clkspec, void *data)
+{
+	struct rs9_driver_data *rs9 = data;
+	unsigned int idx = clkspec->args[0];
+
+	return rs9->clk_dif[idx];
+}
+
+static const struct of_device_id clk_rs9_of_match[];
+
+static int rs9_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	struct device_node *np = client->dev.of_node;
+	unsigned char *name = "DIF0";
+	struct rs9_driver_data *rs9;
+	const char *parent_clk;
+	struct clk_hw *hw;
+	int i, ret;
+
+	rs9 = devm_kzalloc(&client->dev, sizeof(*rs9), GFP_KERNEL);
+	if (!rs9)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, rs9);
+	rs9->client = client;
+	rs9->chip_info = of_device_get_match_data(&client->dev);
+
+	/* Fetch common configuration from DT (if specified) */
+	ret = rs9_get_common_config(rs9);
+	if (ret)
+		return ret;
+
+	/* Fetch DIFx output configuration from DT (if specified) */
+	for (i = 0; i < rs9->chip_info->num_clks; i++) {
+		ret = rs9_get_output_config(rs9, i);
+		if (ret)
+			return ret;
+	}
+
+	/* Mandatory XTal */
+	parent_clk = of_clk_get_parent_name(np, 0);
+	if (!parent_clk)
+		return dev_err_probe(&client->dev, -EINVAL,
+				     "Missing XTal input clock\n");
+
+	rs9->regmap = devm_regmap_init_i2c(client, &rs9_regmap_config);
+	if (IS_ERR(rs9->regmap))
+		return dev_err_probe(&client->dev, PTR_ERR(rs9->regmap),
+				     "Failed to allocate register map\n");
+
+	/* Register clock */
+	for (i = 0; i < rs9->chip_info->num_clks; i++) {
+		name[3]++;
+		hw = clk_hw_register_fixed_factor(&client->dev, name,
+						  parent_clk, 0, 4, 1);
+		if (IS_ERR(hw))
+			return PTR_ERR(hw);
+
+		rs9->clk_dif[i] = hw;
+	}
+
+	ret = devm_of_clk_add_hw_provider(&client->dev, rs9_of_clk_get, rs9);
+	if (!ret)
+		rs9_update_config(rs9);
+
+	return ret;
+}
+
+static int __maybe_unused rs9_suspend(struct device *dev)
+{
+	struct rs9_driver_data *rs9 = dev_get_drvdata(dev);
+
+	regcache_cache_only(rs9->regmap, true);
+	regcache_mark_dirty(rs9->regmap);
+
+	return 0;
+}
+
+static int __maybe_unused rs9_resume(struct device *dev)
+{
+	struct rs9_driver_data *rs9 = dev_get_drvdata(dev);
+	int ret;
+
+	regcache_cache_only(rs9->regmap, false);
+	ret = regcache_sync(rs9->regmap);
+	if (ret)
+		dev_err(dev, "Failed to restore register map: %d\n", ret);
+	return ret;
+}
+
+static const struct rs9_chip_info renesas_9fgv0241_info = {
+	.model		= RENESAS_9FGV0241,
+	.num_clks	= 2,
+};
+
+static const struct i2c_device_id rs9_id[] = {
+	{ "9fgv0241", .driver_data = RENESAS_9FGV0241 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, rs9_id);
+
+static const struct of_device_id clk_rs9_of_match[] = {
+	{ .compatible = "renesas,9fgv0241", .data = &renesas_9fgv0241_info },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, clk_rs9_of_match);
+
+static SIMPLE_DEV_PM_OPS(rs9_pm_ops, rs9_suspend, rs9_resume);
+
+static struct i2c_driver rs9_driver = {
+	.driver = {
+		.name = "clk-renesas-pcie-9series",
+		.pm	= &rs9_pm_ops,
+		.of_match_table = clk_rs9_of_match,
+	},
+	.probe		= rs9_probe,
+	.id_table	= rs9_id,
+};
+module_i2c_driver(rs9_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("Renesas 9-series PCIe clock generator driver");
+MODULE_LICENSE("GPL");