Re: [PATCH v2 06/16] hwmon: (mr75203) fix multi-channel voltage reading

From: Guenter Roeck <linux@roeck-us.net>
To: Eliav Farber <farbere@amazon.com>
Cc: jdelvare@suse.com, robh+dt@kernel.org, mark.rutland@arm.com,
	linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, talel@amazon.com,
	hhhawa@amazon.com, jonnyc@amazon.com, hanochu@amazon.com,
	ronenk@amazon.com, itamark@amazon.com, shellykz@amazon.com,
	shorer@amazon.com, amitlavi@amazon.com, almogbs@amazon.com,
	dwmw@amazon.co.uk, rtanwar@maxlinear.com
Subject: Re: [PATCH v2 06/16] hwmon: (mr75203) fix multi-channel voltage reading
Date: Thu, 18 Aug 2022 13:03:50 -0700	[thread overview]
Message-ID: <20220818200350.GA3287916@roeck-us.net> (raw)
In-Reply-To: <20220817054321.6519-7-farbere@amazon.com>

On Wed, Aug 17, 2022 at 05:43:11AM +0000, Eliav Farber wrote:
> - Fix voltage reading to support number of channels in VM IP (CH_NUM).
> - Configure the ip-polling register to enable polling for all channels.
> 

That fails to explain what is actually wrong in the current code.
Also, one fix per patch, please.

> Signed-off-by: Eliav Farber <farbere@amazon.com>
> ---
>  drivers/hwmon/mr75203.c | 40 +++++++++++++++++++++++++++++++---------
>  1 file changed, 31 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/hwmon/mr75203.c b/drivers/hwmon/mr75203.c
> index bec63b611eb4..4419e481d47c 100644
> --- a/drivers/hwmon/mr75203.c
> +++ b/drivers/hwmon/mr75203.c
> @@ -69,8 +69,9 @@
>  
>  /* VM Individual Macro Register */
>  #define VM_COM_REG_SIZE	0x200
> -#define VM_SDIF_DONE(n)	(VM_COM_REG_SIZE + 0x34 + 0x200 * (n))
> -#define VM_SDIF_DATA(n)	(VM_COM_REG_SIZE + 0x40 + 0x200 * (n))
> +#define VM_SDIF_DONE(vm)	(VM_COM_REG_SIZE + 0x34 + 0x200 * (vm))
> +#define VM_SDIF_DATA(vm, ch)	\
> +	(VM_COM_REG_SIZE + 0x40 + 0x200 * (vm) + 0x4 * (ch))
>  
>  /* SDA Slave Register */
>  #define IP_CTRL			0x00
> @@ -116,6 +117,7 @@ struct pvt_device {
>  	u32			t_num;
>  	u32			p_num;
>  	u32			v_num;
> +	u32			c_num;
>  	u32			ip_freq;
>  	u8			*vm_idx;
>  };
> @@ -181,12 +183,14 @@ static int pvt_read_in(struct device *dev, u32 attr, int channel, long *val)
>  	struct regmap *v_map = pvt->v_map;
>  	u32 n, stat;
>  	u8 vm_idx;
> +	u8 ch_idx;
>  	int ret;
>  
> -	if (channel >= pvt->v_num)
> +	if (channel >= pvt->v_num * pvt->c_num)
>  		return -EINVAL;
>  
> -	vm_idx = pvt->vm_idx[channel];
> +	vm_idx = pvt->vm_idx[channel / pvt->c_num];
> +	ch_idx = channel % pvt->c_num;
>  
>  	switch (attr) {
>  	case hwmon_in_input:
> @@ -197,7 +201,7 @@ static int pvt_read_in(struct device *dev, u32 attr, int channel, long *val)
>  		if (ret)
>  			return ret;
>  
> -		ret = regmap_read(v_map, VM_SDIF_DATA(vm_idx), &n);
> +		ret = regmap_read(v_map, VM_SDIF_DATA(vm_idx, ch_idx), &n);
>  		if(ret < 0)
>  			return ret;
>  
> @@ -386,6 +390,20 @@ static int pvt_init(struct pvt_device *pvt)
>  		if (ret)
>  			return ret;
>  
> +		val = GENMASK(pvt->c_num - 1, 0) | VM_CH_INIT |
> +		      IP_POLL << SDIF_ADDR_SFT |
> +		      SDIF_WRN_W | SDIF_PROG;
> +		ret = regmap_write(v_map, SDIF_W, val);
> +		if (ret < 0)
> +			return ret;
> +
> +		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
> +					       val, !(val & SDIF_BUSY),
> +					       PVT_POLL_DELAY_US,
> +					       PVT_POLL_TIMEOUT_US);
> +		if (ret)
> +			return ret;
> +
>  		val = CFG1_VOL_MEAS_MODE | CFG1_PARALLEL_OUT |
>  		      CFG1_14_BIT | IP_CFG << SDIF_ADDR_SFT |
>  		      SDIF_WRN_W | SDIF_PROG;
> @@ -501,7 +519,7 @@ static int pvt_reset_control_deassert(struct device *dev, struct pvt_device *pvt
>  static int mr75203_probe(struct platform_device *pdev)
>  {
>  	const struct hwmon_channel_info **pvt_info;
> -	u32 ts_num, vm_num, pd_num, val, index, i;
> +	u32 ts_num, vm_num, pd_num, ch_num, val, index, i;
>  	struct device *dev = &pdev->dev;
>  	u32 *temp_config, *in_config;
>  	struct device *hwmon_dev;
> @@ -547,9 +565,11 @@ static int mr75203_probe(struct platform_device *pdev)
>  	ts_num = (val & TS_NUM_MSK) >> TS_NUM_SFT;
>  	pd_num = (val & PD_NUM_MSK) >> PD_NUM_SFT;
>  	vm_num = (val & VM_NUM_MSK) >> VM_NUM_SFT;
> +	ch_num = (val & CH_NUM_MSK) >> CH_NUM_SFT;
>  	pvt->t_num = ts_num;
>  	pvt->p_num = pd_num;
>  	pvt->v_num = vm_num;
> +	pvt->c_num = ch_num;
>  	val = 0;
>  	if (ts_num)
>  		val++;
> @@ -586,6 +606,8 @@ static int mr75203_probe(struct platform_device *pdev)
>  	}
>  
>  	if (vm_num) {
> +		u32 total_ch = ch_num * vm_num;
> +
>  		ret = pvt_get_regmap(pdev, "vm", pvt);
>  		if (ret)
>  			return ret;
> @@ -614,13 +636,13 @@ static int mr75203_probe(struct platform_device *pdev)
>  			pvt->v_num = i;
>  		}
>  
> -		in_config = devm_kcalloc(dev, vm_num + 1,
> +		in_config = devm_kcalloc(dev, total_ch + 1,
>  					 sizeof(*in_config), GFP_KERNEL);
>  		if (!in_config)
>  			return -ENOMEM;
>  
> -		memset32(in_config, HWMON_I_INPUT, vm_num);
> -		in_config[vm_num] = 0;
> +		memset32(in_config, HWMON_I_INPUT, total_ch);
> +		in_config[total_ch] = 0;
>  		pvt_in.config = in_config;
>  
>  		pvt_info[index++] = &pvt_in;