diff options
Diffstat (limited to 'drivers/mfd/da9052-i2c.c')
| -rw-r--r-- | drivers/mfd/da9052-i2c.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/mfd/da9052-i2c.c b/drivers/mfd/da9052-i2c.c index ac74a4d1dae..6a9fec40d01 100644 --- a/drivers/mfd/da9052-i2c.c +++ b/drivers/mfd/da9052-i2c.c @@ -27,6 +27,65 @@ #include <linux/of_device.h> #endif +/* I2C safe register check */ +static inline bool i2c_safe_reg(unsigned char reg) +{ + switch (reg) { + case DA9052_STATUS_A_REG: + case DA9052_STATUS_B_REG: + case DA9052_STATUS_C_REG: + case DA9052_STATUS_D_REG: + case DA9052_ADC_RES_L_REG: + case DA9052_ADC_RES_H_REG: + case DA9052_VDD_RES_REG: + case DA9052_ICHG_AV_REG: + case DA9052_TBAT_RES_REG: + case DA9052_ADCIN4_RES_REG: + case DA9052_ADCIN5_RES_REG: + case DA9052_ADCIN6_RES_REG: + case DA9052_TJUNC_RES_REG: + case DA9052_TSI_X_MSB_REG: + case DA9052_TSI_Y_MSB_REG: + case DA9052_TSI_LSB_REG: + case DA9052_TSI_Z_MSB_REG: + return true; + default: + return false; + } +} + +/* + * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC + * gets lockup up or fails to respond following a system reset. + * This fix is to follow any read or write with a dummy read to a safe + * register. + */ +static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg) +{ + int val; + + switch (da9052->chip_id) { + case DA9052: + case DA9053_AA: + case DA9053_BA: + case DA9053_BB: + /* A dummy read to a safe register address. */ + if (!i2c_safe_reg(reg)) + return regmap_read(da9052->regmap, + DA9052_PARK_REGISTER, + &val); + break; + default: + /* + * For other chips parking of I2C register + * to a safe place is not required. + */ + break; + } + + return 0; +} + static int da9052_i2c_enable_multiwrite(struct da9052 *da9052) { int reg_val, ret; @@ -83,6 +142,7 @@ static int da9052_i2c_probe(struct i2c_client *client, da9052->dev = &client->dev; da9052->chip_irq = client->irq; + da9052->fix_io = da9052_i2c_fix; i2c_set_clientdata(client, da9052); |