Re: [PATCH v5 10/10] mfd: mt6360: Merge different sub-devices I2C read/write

Gene Chen
2020-10-27T09:37:06Z

Dear Reviewers,

Does any comments about this patch v5 10/10?

Gene Chen <gene.chen.richtek@gmail.com> 於 2020年9月22日 週二 下午6:21寫道：

>
> From: Gene Chen <gene_chen@richtek.com>
>
> Merge different sub-devices I2C read/write functions into one Regmap,
> because PMIC and LDO part need CRC bits for access protection.
>
> Signed-off-by: Gene Chen <gene_chen@richtek.com>
> ---
> drivers/mfd/Kconfig | 1 +
> drivers/mfd/mt6360-core.c | 224 ++++++++++++++++++++++++++++++++++++++--------
> 2 files changed, 190 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 33df083..1dfe446 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -913,6 +913,7 @@ config MFD_MT6360
> select MFD_CORE
> select REGMAP_I2C
> select REGMAP_IRQ
> + select CRC8
> depends on I2C
> help
> Say Y here to enable MT6360 PMU/PMIC/LDO functional support.
> diff --git a/drivers/mfd/mt6360-core.c b/drivers/mfd/mt6360-core.c
> index 075b466..2ec9559 100644
> --- a/drivers/mfd/mt6360-core.c
> +++ b/drivers/mfd/mt6360-core.c
> @@ -62,6 +62,18 @@ struct mt6360_ddata {
>
> #define MT6360_CRC8_POLYNOMIAL 0x7
>
> +#define MT6360_CRC_I2C_ADDR_SIZE 1
> +#define MT6360_CRC_REG_ADDR_SIZE 1
> +/* prealloca read size = i2c device addr + i2c reg addr + val ... + crc8 */
> +#define MT6360_ALLOC_READ_SIZE(_size) (_size + 3)
> +/* prealloca write size = i2c device addr + i2c reg addr + val ... + crc8 + dummy byte */
> +#define MT6360_ALLOC_WRITE_SIZE(_size) (_size + 4)
> +#define MT6360_CRC_PREDATA_OFFSET (MT6360_CRC_I2C_ADDR_SIZE + MT6360_CRC_REG_ADDR_SIZE)
> +#define MT6360_CRC_CRC8_SIZE 1
> +#define MT6360_CRC_DUMMY_BYTE_SIZE 1
> +#define MT6360_REGMAP_REG_BYTE_SIZE 2
> +#define I2C_ADDR_XLATE_8BIT(_addr, _rw) (((_addr & 0x7F) << 1) + _rw)
> +
> /* reg 0 -> 0 ~ 7 */
> #define MT6360_CHG_TREG_EVT 4
> #define MT6360_CHG_AICR_EVT 5
> @@ -266,12 +278,6 @@ static const struct regmap_irq_chip mt6360_irq_chip = {
> .use_ack = true,
> };
>
> -static const struct regmap_config mt6360_pmu_regmap_config = {
> - .reg_bits = 8,
> - .val_bits = 8,
> - .max_register = MT6360_PMU_MAXREG,
> -};
> -
> static const struct resource mt6360_adc_resources[] = {
> DEFINE_RES_IRQ_NAMED(MT6360_ADC_DONEI, "adc_donei"),
> };
> @@ -334,7 +340,7 @@ static const struct mfd_cell mt6360_devs[] = {
> OF_MFD_CELL("mt6360-led", mt6360_led_resources,
> NULL, 0, 0, "mediatek,mt6360-led"),
> OF_MFD_CELL("mt6360-regulator", mt6360_regulator_resources,
> - NULL, 0, 0, "mediatek,mt6360-regulator"),
> + NULL, 0, 0, NULL),
> OF_MFD_CELL("mt6360-tcpc", NULL,
> NULL, 0, 0, "mediatek,mt6360-tcpc"),
> };
> @@ -349,7 +355,7 @@ static int mt6360_check_vendor_info(struct mt6360_ddata *ddata)
> return ret;
>
> if ((info & CHIP_VEN_MASK) != CHIP_VEN_MT6360) {
> - dev_err(&client->dev, "Device not supported\n");
> + dev_err(ddata->dev, "Device not supported\n");
> return -ENODEV;
> }
>
> @@ -358,11 +364,161 @@ static int mt6360_check_vendor_info(struct mt6360_ddata *ddata)
> return 0;
> }
>
> -static const unsigned short mt6360_slave_addr[MT6360_SLAVE_MAX] = {
> - MT6360_PMU_SLAVEID,
> +static const unsigned short mt6360_slave_addrs[MT6360_SLAVE_MAX] = {
> + MT6360_TCPC_SLAVEID,
> MT6360_PMIC_SLAVEID,
> MT6360_LDO_SLAVEID,
> - MT6360_TCPC_SLAVEID,
> + MT6360_PMU_SLAVEID,
> +};
> +
> +static int mt6360_xlate_pmicldo_addr(u8 *addr, int rw_size)
> +{
> + /* Address is already in encoded [5:0] */
> + *addr &= MT6360_ADDRESS_MASK;
> +
> + switch (rw_size) {
> + case 1:
> + *addr |= MT6360_DATA_SIZE_1_BYTE;
> + break;
> + case 2:
> + *addr |= MT6360_DATA_SIZE_2_BYTES;
> + break;
> + case 3:
> + *addr |= MT6360_DATA_SIZE_3_BYTES;
> + break;
> + case 4:
> + *addr |= MT6360_DATA_SIZE_4_BYTES;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_regmap_read(void *context, const void *reg, size_t reg_size,
> + void *val, size_t val_size)
> +{
> + struct mt6360_ddata *ddata = context;
> + u8 bank = *(u8 *)reg;
> + u8 reg_addr = *(u8 *)(reg + 1);
> + struct i2c_client *i2c = ddata->i2c[bank];
> + bool crc_needed = false;
> + u8 *buf;
> + int buf_len = MT6360_ALLOC_READ_SIZE(val_size);
> + int read_size = val_size;
> + u8 crc;
> + int ret;
> +
> + if (bank == MT6360_SLAVE_PMIC || bank == MT6360_SLAVE_LDO) {
> + crc_needed = true;
> + ret = mt6360_xlate_pmicldo_addr(&reg_addr, val_size);
> + if (ret < 0)
> + return ret;
> + read_size += MT6360_CRC_CRC8_SIZE;
> + }
> +
> + buf = kzalloc(buf_len, GFP_KERNEL);
> + if (!buf)
> + return -ENOMEM;
> +
> + buf[0] = I2C_ADDR_XLATE_8BIT(i2c->addr, I2C_SMBUS_READ);
> + buf[1] = reg_addr;
> +
> + ret = i2c_smbus_read_i2c_block_data(i2c, reg_addr, read_size,
> + buf + MT6360_CRC_PREDATA_OFFSET);
> + if (ret < 0)
> + goto out;
> + else if (ret != read_size) {
> + ret = -EIO;
> + goto out;
> + }
> +
> + if (crc_needed) {
> + crc = crc8(ddata->crc8_tbl, buf, val_size + MT6360_CRC_PREDATA_OFFSET, 0);
> + if (crc != buf[val_size + MT6360_CRC_PREDATA_OFFSET]) {
> + ret = -EIO;
> + goto out;
> + }
> + }
> +
> + memcpy(val, buf + MT6360_CRC_PREDATA_OFFSET, val_size);
> +out:
> + kfree(buf);
> + return (ret < 0) ? ret : 0;
> +}
> +
> +static int mt6360_regmap_write(void *context, const void *val, size_t val_size)
> +{
> + struct mt6360_ddata *ddata = context;
> + u8 bank = *(u8 *)val;
> + u8 reg_addr = *(u8 *)(val + 1);
> + struct i2c_client *i2c = ddata->i2c[bank];
> + bool crc_needed = false;
> + u8 *buf;
> + int buf_len = MT6360_ALLOC_WRITE_SIZE(val_size);
> + int write_size = val_size - MT6360_REGMAP_REG_BYTE_SIZE;
> + int ret;
> +
> + if (bank == MT6360_SLAVE_PMIC || bank == MT6360_SLAVE_LDO) {
> + crc_needed = true;
> + ret = mt6360_xlate_pmicldo_addr(&reg_addr, val_size - MT6360_REGMAP_REG_BYTE_SIZE);
> + if (ret < 0)
> + return ret;
> + }
> +
> + buf = kzalloc(buf_len, GFP_KERNEL);
> + if (!buf)
> + return -ENOMEM;
> +
> + buf[0] = I2C_ADDR_XLATE_8BIT(i2c->addr, I2C_SMBUS_WRITE);
> + buf[1] = reg_addr;
> + memcpy(buf + MT6360_CRC_PREDATA_OFFSET, val + MT6360_REGMAP_REG_BYTE_SIZE, write_size);
> +
> + if (crc_needed) {
> + buf[val_size] = crc8(ddata->crc8_tbl, buf, val_size, 0);
> + write_size += (MT6360_CRC_CRC8_SIZE + MT6360_CRC_DUMMY_BYTE_SIZE);
> + }
> +
> + ret = i2c_smbus_write_i2c_block_data(i2c, reg_addr, write_size,
> + buf + MT6360_CRC_PREDATA_OFFSET);
> +
> + kfree(buf);
> + return ret;
> +}
> +
> +static const struct regmap_bus mt6360_regmap_bus = {
> + .read = mt6360_regmap_read,
> + .write = mt6360_regmap_write,
> +
> + /* Due to PMIC and LDO CRC access size limit */
> + .max_raw_read = 4,
> + .max_raw_write = 4,
> +};
> +
> +static bool mt6360_is_readwrite_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case MT6360_REG_TCPCSTART ... MT6360_REG_TCPCEND:
> + fallthrough;
> + case MT6360_REG_PMICSTART ... MT6360_REG_PMICEND:
> + fallthrough;
> + case MT6360_REG_LDOSTART ... MT6360_REG_LDOEND:
> + fallthrough;
> + case MT6360_REG_PMUSTART ... MT6360_REG_PMUEND:
> + return true;
> + }
> +
> + return false;
> +}
> +
> +static const struct regmap_config mt6360_regmap_config = {
> + .reg_bits = 16,
> + .val_bits = 8,
> + .reg_format_endian = REGMAP_ENDIAN_BIG,
> + .max_register = MT6360_REG_PMUEND,
> + .writeable_reg = mt6360_is_readwrite_reg,
> + .readable_reg = mt6360_is_readwrite_reg,
> };
>
> static int mt6360_probe(struct i2c_client *client)
> @@ -375,9 +531,23 @@ static int mt6360_probe(struct i2c_client *client)
> return -ENOMEM;
>
> ddata->dev = &client->dev;
> - i2c_set_clientdata(client, ddata);
>
> - ddata->regmap = devm_regmap_init_i2c(client, &mt6360_pmu_regmap_config);
> + for (i = 0; i < MT6360_SLAVE_MAX - 1; i++) {
> + ddata->i2c[i] = devm_i2c_new_dummy_device(&client->dev,
> + client->adapter,
> + mt6360_slave_addrs[i]);
> + if (IS_ERR(ddata->i2c[i])) {
> + dev_err(&client->dev,
> + "Failed to get new dummy I2C device for address 0x%x",
> + mt6360_slave_addrs[i]);
> + return PTR_ERR(ddata->i2c[i]);
> + }
> + }
> + ddata->i2c[MT6360_SLAVE_MAX - 1] = client;
> +
> + crc8_populate_msb(ddata->crc8_tbl, MT6360_CRC8_POLYNOMIAL);
> + ddata->regmap = devm_regmap_init(ddata->dev, &mt6360_regmap_bus, ddata,
> + &mt6360_regmap_config);
> if (IS_ERR(ddata->regmap)) {
> dev_err(&client->dev, "Failed to register regmap\n");
> return PTR_ERR(ddata->regmap);
> @@ -387,34 +557,18 @@ static int mt6360_probe(struct i2c_client *client)
> if (ret)
> return ret;
>
> - ret = devm_regmap_add_irq_chip(&client->dev, ddata->regmap, client->irq,
> - 0, 0, &mt6360_irq_chip,
> - &ddata->irq_data);
> + ret = devm_regmap_add_irq_chip(&client->dev, ddata->regmap, client->irq, 0, 0,
> + &mt6360_irq_chip, &ddata->irq_data);
> if (ret) {
> dev_err(&client->dev, "Failed to add Regmap IRQ Chip\n");
> return ret;
> }
>
> - ddata->i2c[0] = client;
> - for (i = 1; i < MT6360_SLAVE_MAX; i++) {
> - ddata->i2c[i] = devm_i2c_new_dummy_device(&client->dev,
> - client->adapter,
> - mt6360_slave_addr[i]);
> - if (IS_ERR(ddata->i2c[i])) {
> - dev_err(&client->dev,
> - "Failed to get new dummy I2C device for address 0x%x",
> - mt6360_slave_addr[i]);
> - return PTR_ERR(ddata->i2c[i]);
> - }
> - i2c_set_clientdata(ddata->i2c[i], ddata);
> - }
> -
> - ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_AUTO,
> - mt6360_devs, ARRAY_SIZE(mt6360_devs), NULL,
> - 0, regmap_irq_get_domain(ddata->irq_data));
> + ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_AUTO, mt6360_devs,
> + ARRAY_SIZE(mt6360_devs), NULL, 0,
> + regmap_irq_get_domain(ddata->irq_data));
> if (ret) {
> - dev_err(&client->dev,
> - "Failed to register subordinate devices\n");
> + dev_err(&client->dev, "Failed to register subordinate devices\n");
> return ret;
> }
>
> --
> 2.7.4
>