Re: [PATCH v6 6/9] rtc: abx80x: use regmap instead of I2C specific API

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] abx80x_read_alarm() unconditionally fails and returns -EIO because of a leftover partial-read check.
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commit 927241f9edd452c16c2bc8ee202f13c63e681b56
Author: Antoni Pokusinski <apokusinski01@gmail.com>

rtc: abx80x: use regmap instead of I2C specific API

This commit refactors the abx80x RTC driver to use the regmap API
instead of the i2c_smbus_* functions. This abstraction prepares the
driver for future SPI support for ABX81X RTCs.

> diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c
> --- a/drivers/rtc/rtc-abx80x.c
> +++ b/drivers/rtc/rtc-abx80x.c
> @@ -305,25 +308,24 @@ static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
>  
>  static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
>  {
> -	struct i2c_client *client = to_i2c_client(dev);
> -	struct abx80x_priv *priv = i2c_get_clientdata(client);
> +	struct abx80x_priv *priv = dev_get_drvdata(dev);
>  	unsigned char buf[7];
>  
> -	int irq_mask, err;
> +	unsigned int irq_mask;
> +	int err;
>  
>  	if (priv->irq <= 0)
>  		return -EINVAL;
>  
> -	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
> -					    sizeof(buf), buf);
> -	if (err < 0)
> +	err = regmap_bulk_read(priv->regmap, ABX8XX_REG_ASC, buf, sizeof(buf));
> +	if (err)
>  		return err;
>  	if (err < ARRAY_SIZE(buf))
>  		return -EIO;

[Severity: High]
Does this inadvertently fail on all successful reads?

The legacy i2c_smbus_read_i2c_block_data() function returned the number of
bytes read, but regmap_bulk_read() returns 0 on success. Because
ARRAY_SIZE(buf) is 7, a successful regmap read where err == 0 will satisfy
the err < ARRAY_SIZE(buf) condition, causing abx80x_read_alarm() to always
return -EIO.

Should this partial-read check be removed entirely now that the driver uses
regmap_bulk_read()?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260907203216.53192-1-apokusinski01@gmail.com?part=6