hwmon: (mr75203) fix multi-channel voltage reading

Fix voltage allocation and reading to support all channels in all VMs.
Prior to this change allocation and reading were done only for the first
channel in each VM.
This change counts the total number of channels for allocation, and takes
into account the channel offset when reading the sample data register.

Fixes: 9d82335 ("hwmon: Add hardware monitoring driver for Moortec MR75203 PVT controller")
Signed-off-by: Eliav Farber <farbere@amazon.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220908152449.35457-6-farbere@amazon.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/mr75203.c

@@ -68,8 +68,9 @@
 
 /* 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
@@ -115,6 +116,7 @@ struct pvt_device {
 	u32			t_num;
 	u32			p_num;
 	u32			v_num;
+	u32			c_num;
 	u32			ip_freq;
 	u8			*vm_idx;
 };
@@ -178,14 +180,15 @@ static int pvt_read_in(struct device *dev, u32 attr, int channel, long *val)
 {
 	struct pvt_device *pvt = dev_get_drvdata(dev);
 	struct regmap *v_map = pvt->v_map;
+	u8 vm_idx, ch_idx;
 	u32 n, stat;
-	u8 vm_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:
@@ -196,7 +199,7 @@ 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;
 
@@ -499,8 +502,8 @@ static int pvt_reset_control_deassert(struct device *dev, struct pvt_device *pvt
 
 static int mr75203_probe(struct platform_device *pdev)
 {
+	u32 ts_num, vm_num, pd_num, ch_num, val, index, i;
 	const struct hwmon_channel_info **pvt_info;
-	u32 ts_num, vm_num, pd_num, val, index, i;
 	struct device *dev = &pdev->dev;
 	u32 *temp_config, *in_config;
 	struct device *hwmon_dev;
@@ -541,9 +544,11 @@ 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++;
@@ -580,7 +585,7 @@ static int mr75203_probe(struct platform_device *pdev)
 	}
 
 	if (vm_num) {
-		u32 num = vm_num;
+		u32 total_ch;
 
 		ret = pvt_get_regmap(pdev, "vm", pvt);
 		if (ret)
@@ -604,20 +609,20 @@ static int mr75203_probe(struct platform_device *pdev)
 			for (i = 0; i < vm_num; i++)
 				if (pvt->vm_idx[i] >= vm_num ||
 				    pvt->vm_idx[i] == 0xff) {
-					num = i;
 					pvt->v_num = i;
 					vm_num = i;
 					break;
 				}
 		}
 
-		in_config = devm_kcalloc(dev, num + 1,
+		total_ch = ch_num * vm_num;
+		in_config = devm_kcalloc(dev, total_ch + 1,
 					 sizeof(*in_config), GFP_KERNEL);
 		if (!in_config)
 			return -ENOMEM;
 
-		memset32(in_config, HWMON_I_INPUT, num);
-		in_config[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;