Re: [PATCH mfd v1 1/2] mfd: rsmu: support I2C SMBus access

From: Lee Jones
Date: Fri Apr 12 2024 - 03:44:04 EST


On Thu, 11 Apr 2024, Min Li wrote:

> From: Min Li <min.li.xe@xxxxxxxxxxx>
>
> 8a3400x device implements its own reg_read and reg_write,
> which only supports I2C bus access. This patch adds support
> for SMBus access.
>
> Signed-off-by: Min Li <min.li.xe@xxxxxxxxxxx>
> ---
> send the patch series as --thread suggested by Lee

These are still not connected.

> drivers/mfd/rsmu_i2c.c | 107 +++++++++++++++++++++++++++++++++++------
> drivers/mfd/rsmu_spi.c | 8 +--
> 2 files changed, 97 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/mfd/rsmu_i2c.c b/drivers/mfd/rsmu_i2c.c
> index 5711e512b..cba64f107 100644
> --- a/drivers/mfd/rsmu_i2c.c
> +++ b/drivers/mfd/rsmu_i2c.c
> @@ -32,6 +32,8 @@
> #define RSMU_SABRE_PAGE_ADDR 0x7F
> #define RSMU_SABRE_PAGE_WINDOW 128
>
> +typedef int (*rsmu_rw_device)(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes);
> +
> static const struct regmap_range_cfg rsmu_sabre_range_cfg[] = {
> {
> .range_min = 0,
> @@ -54,7 +56,28 @@ static bool rsmu_sabre_volatile_reg(struct device *dev, unsigned int reg)
> }
> }
>
> -static int rsmu_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes)
> +static int rsmu_smbus_i2c_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes)
> +{
> + struct i2c_client *client = to_i2c_client(rsmu->dev);
> +
> + return i2c_smbus_write_i2c_block_data(client, reg, bytes, buf);
> +}
> +
> +static int rsmu_smbus_i2c_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes)
> +{
> + struct i2c_client *client = to_i2c_client(rsmu->dev);
> + int ret;
> +
> + ret = i2c_smbus_read_i2c_block_data(client, reg, bytes, buf);
> + if (ret == bytes)
> + return 0;
> + else if (ret < 0)
> + return ret;
> + else
> + return -EIO;
> +}
> +
> +static int rsmu_i2c_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes)
> {
> struct i2c_client *client = to_i2c_client(rsmu->dev);
> struct i2c_msg msg[2];
> @@ -84,10 +107,11 @@ static int rsmu_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes)
> return 0;
> }
>
> -static int rsmu_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes)
> +static int rsmu_i2c_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes)
> {
> struct i2c_client *client = to_i2c_client(rsmu->dev);
> - u8 msg[RSMU_MAX_WRITE_COUNT + 1]; /* 1 Byte added for the device register */
> + /* we add 1 byte for device register */
> + u8 msg[RSMU_MAX_WRITE_COUNT + 1];
> int cnt;
>
> if (bytes > RSMU_MAX_WRITE_COUNT)
> @@ -107,7 +131,8 @@ static int rsmu_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes
> return 0;
> }
>
> -static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg)
> +static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg,
> + rsmu_rw_device rsmu_write_device)
> {
> u32 page = reg & RSMU_CM_PAGE_MASK;
> u8 buf[4];
> @@ -136,35 +161,35 @@ static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg)
> return err;
> }
>
> -static int rsmu_reg_read(void *context, unsigned int reg, unsigned int *val)
> +static int rsmu_i2c_reg_read(void *context, unsigned int reg, unsigned int *val)
> {
> struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
> u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
> int err;
>
> - err = rsmu_write_page_register(rsmu, reg);
> + err = rsmu_write_page_register(rsmu, reg, rsmu_i2c_write_device);
> if (err)
> return err;
>
> - err = rsmu_read_device(rsmu, addr, (u8 *)val, 1);
> + err = rsmu_i2c_read_device(rsmu, addr, (u8 *)val, 1);
> if (err)
> dev_err(rsmu->dev, "Failed to read offset address 0x%x\n", addr);
>
> return err;
> }
>
> -static int rsmu_reg_write(void *context, unsigned int reg, unsigned int val)
> +static int rsmu_i2c_reg_write(void *context, unsigned int reg, unsigned int val)
> {
> struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
> u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
> u8 data = (u8)val;
> int err;
>
> - err = rsmu_write_page_register(rsmu, reg);
> + err = rsmu_write_page_register(rsmu, reg, rsmu_i2c_write_device);
> if (err)
> return err;
>
> - err = rsmu_write_device(rsmu, addr, &data, 1);
> + err = rsmu_i2c_write_device(rsmu, addr, &data, 1);
> if (err)
> dev_err(rsmu->dev,
> "Failed to write offset address 0x%x\n", addr);
> @@ -172,12 +197,57 @@ static int rsmu_reg_write(void *context, unsigned int reg, unsigned int val)
> return err;
> }
>
> -static const struct regmap_config rsmu_cm_regmap_config = {
> +static int rsmu_smbus_i2c_reg_read(void *context, unsigned int reg, unsigned int *val)
> +{
> + struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
> + u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
> + int err;
> +
> + err = rsmu_write_page_register(rsmu, reg, rsmu_smbus_i2c_write_device);
> + if (err)
> + return err;
> +
> + err = rsmu_smbus_i2c_read_device(rsmu, addr, (u8 *)val, 1);
> + if (err)
> + dev_err(rsmu->dev, "Failed to read offset address 0x%x\n", addr);
> +
> + return err;
> +}
> +
> +static int rsmu_smbus_i2c_reg_write(void *context, unsigned int reg, unsigned int val)
> +{
> + struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
> + u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
> + u8 data = (u8)val;
> + int err;
> +
> + err = rsmu_write_page_register(rsmu, reg, rsmu_smbus_i2c_write_device);
> + if (err)
> + return err;
> +
> + err = rsmu_smbus_i2c_write_device(rsmu, addr, &data, 1);
> + if (err)
> + dev_err(rsmu->dev,
> + "Failed to write offset address 0x%x\n", addr);
> +
> + return err;
> +}
> +
> +static const struct regmap_config rsmu_i2c_cm_regmap_config = {
> .reg_bits = 32,
> .val_bits = 8,
> .max_register = 0x20120000,
> - .reg_read = rsmu_reg_read,
> - .reg_write = rsmu_reg_write,
> + .reg_read = rsmu_i2c_reg_read,
> + .reg_write = rsmu_i2c_reg_write,
> + .cache_type = REGCACHE_NONE,
> +};
> +
> +static const struct regmap_config rsmu_smbus_i2c_cm_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 8,
> + .max_register = 0x20120000,
> + .reg_read = rsmu_smbus_i2c_reg_read,
> + .reg_write = rsmu_smbus_i2c_reg_write,
> .cache_type = REGCACHE_NONE,
> };
>
> @@ -219,7 +289,15 @@ static int rsmu_i2c_probe(struct i2c_client *client)
>
> switch (rsmu->type) {
> case RSMU_CM:
> - cfg = &rsmu_cm_regmap_config;
> + if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> + cfg = &rsmu_i2c_cm_regmap_config;
> + } else if (i2c_check_functionality(client->adapter,
> + I2C_FUNC_SMBUS_I2C_BLOCK)) {
> + cfg = &rsmu_smbus_i2c_cm_regmap_config;
> + } else {
> + dev_err(rsmu->dev, "Unsupported i2c adapter\n");
> + return -ENOTSUPP;
> + }
> break;
> case RSMU_SABRE:
> cfg = &rsmu_sabre_regmap_config;
> @@ -236,6 +314,7 @@ static int rsmu_i2c_probe(struct i2c_client *client)
> rsmu->regmap = devm_regmap_init(&client->dev, NULL, client, cfg);
> else
> rsmu->regmap = devm_regmap_init_i2c(client, cfg);
> +
> if (IS_ERR(rsmu->regmap)) {
> ret = PTR_ERR(rsmu->regmap);
> dev_err(rsmu->dev, "Failed to allocate register map: %d\n", ret);
> diff --git a/drivers/mfd/rsmu_spi.c b/drivers/mfd/rsmu_spi.c
> index ca0a1202c..39d9be1e1 100644
> --- a/drivers/mfd/rsmu_spi.c
> +++ b/drivers/mfd/rsmu_spi.c
> @@ -106,10 +106,10 @@ static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg)
> return 0;
> page_reg = RSMU_CM_PAGE_ADDR;
> page = reg & RSMU_PAGE_MASK;
> - buf[0] = (u8)(page & 0xff);
> - buf[1] = (u8)((page >> 8) & 0xff);
> - buf[2] = (u8)((page >> 16) & 0xff);
> - buf[3] = (u8)((page >> 24) & 0xff);
> + buf[0] = (u8)(page & 0xFF);
> + buf[1] = (u8)((page >> 8) & 0xFF);
> + buf[2] = (u8)((page >> 16) & 0xFF);
> + buf[3] = (u8)((page >> 24) & 0xFF);
> bytes = 4;
> break;
> case RSMU_SABRE:
> --
> 2.39.2
>

--
Lee Jones [李琼斯]