Re: [PATCH v4 1/7] mfd: rk808: fix up the chip id get failed

[Lee Jones]

On Fri, 17 Mar 2017, Elaine Zhang wrote:

> the rk8xx chip id is:
> ((MSB << 8) | LSB) & 0xfff0
> 
> Signed-off-by: Elaine Zhang <zhangqing@xxxxxxxxxxxxxx>
> ---
>  drivers/mfd/rk808.c       | 21 +++++++++++++++------
>  include/linux/mfd/rk808.h |  1 +
>  2 files changed, 16 insertions(+), 6 deletions(-)

For my own reference:
  Acked-for-MFD-by: Lee Jones <lee.jones@xxxxxxxxxx>
  
> diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
> index fd087cbb0bde..3334a2a7f3fb 100644
> --- a/drivers/mfd/rk808.c
> +++ b/drivers/mfd/rk808.c
> @@ -325,7 +325,7 @@ static int rk808_probe(struct i2c_client *client,
>  	void (*pm_pwroff_fn)(void);
>  	int nr_pre_init_regs;
>  	int nr_cells;
> -	int pm_off = 0;
> +	int pm_off = 0, msb, lsb;
>  	int ret;
>  	int i;
>  
> @@ -333,14 +333,23 @@ static int rk808_probe(struct i2c_client *client,
>  	if (!rk808)
>  		return -ENOMEM;
>  
> -	rk808->variant = i2c_smbus_read_word_data(client, RK808_ID_MSB);
> -	if (rk808->variant < 0) {
> -		dev_err(&client->dev, "Failed to read the chip id at 0x%02x\n",
> +	/* read Chip variant */
> +	msb = i2c_smbus_read_byte_data(client, RK808_ID_MSB);
> +	if (msb < 0) {
> +		dev_err(&client->dev, "failed to read the chip id at 0x%x\n",
>  			RK808_ID_MSB);
> -		return rk808->variant;
> +		return msb;
>  	}
>  
> -	dev_dbg(&client->dev, "Chip id: 0x%x\n", (unsigned int)rk808->variant);
> +	lsb = i2c_smbus_read_byte_data(client, RK808_ID_LSB);
> +	if (lsb < 0) {
> +		dev_err(&client->dev, "failed to read the chip id at 0x%x\n",
> +			RK808_ID_LSB);
> +		return lsb;
> +	}
> +
> +	rk808->variant = ((msb << 8) | lsb) & RK8XX_ID_MSK;
> +	dev_info(&client->dev, "Chip id: 0x%x\n", (unsigned int)rk808->variant);
>  
>  	switch (rk808->variant) {
>  	case RK808_ID:
> diff --git a/include/linux/mfd/rk808.h b/include/linux/mfd/rk808.h
> index 83701ef7d3c7..54feb140c210 100644
> --- a/include/linux/mfd/rk808.h
> +++ b/include/linux/mfd/rk808.h
> @@ -298,6 +298,7 @@ enum rk818_reg {
>  #define VOUT_LO_INT	BIT(0)
>  #define CLK32KOUT2_EN	BIT(0)
>  
> +#define RK8XX_ID_MSK			0xfff0
>  enum {
>  	BUCK_ILMIN_50MA,
>  	BUCK_ILMIN_100MA,

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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