[PATCH v2 3/3] hwmon: (k10temp): Show errors failing to read

[Mario Limonciello <mario.limonciello@xxxxxxx>]

Enabling Yellow Carp was initially not working "properly"
because extra IDs were needed, but this wasn't obvious because fail values
from `amd_smn_read` were ignored.

Don't discard errors from any functions providing them, instead pass up
to the caller.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
 drivers/hwmon/k10temp.c | 87 ++++++++++++++++++++++++-----------------
 1 file changed, 52 insertions(+), 35 deletions(-)

diff --git a/drivers/hwmon/k10temp.c b/drivers/hwmon/k10temp.c
index 38bc35ac8135..2edb49d39d22 100644
--- a/drivers/hwmon/k10temp.c
+++ b/drivers/hwmon/k10temp.c
@@ -98,8 +98,8 @@ static DEFINE_MUTEX(nb_smu_ind_mutex);
 
 struct k10temp_data {
 	struct pci_dev *pdev;
-	void (*read_htcreg)(struct pci_dev *pdev, u32 *regval);
-	void (*read_tempreg)(struct pci_dev *pdev, u32 *regval);
+	int (*read_htcreg)(struct pci_dev *pdev, u32 *regval);
+	int (*read_tempreg)(struct pci_dev *pdev, u32 *regval);
 	int temp_offset;
 	u32 temp_adjust_mask;
 	u32 show_temp;
@@ -129,55 +129,65 @@ static const struct tctl_offset tctl_offset_table[] = {
 	{ 0x17, "AMD Ryzen Threadripper 29", 27000 }, /* 29{20,50,70,90}[W]X */
 };
 
-static void read_htcreg_pci(struct pci_dev *pdev, u32 *regval)
+static int read_htcreg_pci(struct pci_dev *pdev, u32 *regval)
 {
-	pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, regval);
+	return pci_read_config_dword(pdev, REG_HARDWARE_THERMAL_CONTROL, regval);
 }
 
-static void read_tempreg_pci(struct pci_dev *pdev, u32 *regval)
+static int read_tempreg_pci(struct pci_dev *pdev, u32 *regval)
 {
-	pci_read_config_dword(pdev, REG_REPORTED_TEMPERATURE, regval);
+	return pci_read_config_dword(pdev, REG_REPORTED_TEMPERATURE, regval);
 }
 
-static void amd_nb_index_read(struct pci_dev *pdev, unsigned int devfn,
+static int amd_nb_index_read(struct pci_dev *pdev, unsigned int devfn,
 			      unsigned int base, int offset, u32 *val)
 {
+	int ret;
+
 	mutex_lock(&nb_smu_ind_mutex);
-	pci_bus_write_config_dword(pdev->bus, devfn,
-				   base, offset);
-	pci_bus_read_config_dword(pdev->bus, devfn,
-				  base + 4, val);
+	ret = pci_bus_write_config_dword(pdev->bus, devfn,
+					 base, offset);
+	if (ret)
+		goto out;
+	ret = pci_bus_read_config_dword(pdev->bus, devfn,
+					base + 4, val);
+out:
 	mutex_unlock(&nb_smu_ind_mutex);
+	return ret;
 }
 
-static void read_htcreg_nb_f15(struct pci_dev *pdev, u32 *regval)
+static int read_htcreg_nb_f15(struct pci_dev *pdev, u32 *regval)
 {
-	amd_nb_index_read(pdev, PCI_DEVFN(0, 0), 0xb8,
-			  F15H_M60H_HARDWARE_TEMP_CTRL_OFFSET, regval);
+	return amd_nb_index_read(pdev, PCI_DEVFN(0, 0), 0xb8,
+				F15H_M60H_HARDWARE_TEMP_CTRL_OFFSET, regval);
 }
 
-static void read_tempreg_nb_f15(struct pci_dev *pdev, u32 *regval)
+static int read_tempreg_nb_f15(struct pci_dev *pdev, u32 *regval)
 {
-	amd_nb_index_read(pdev, PCI_DEVFN(0, 0), 0xb8,
-			  F15H_M60H_REPORTED_TEMP_CTRL_OFFSET, regval);
+	return amd_nb_index_read(pdev, PCI_DEVFN(0, 0), 0xb8,
+				F15H_M60H_REPORTED_TEMP_CTRL_OFFSET, regval);
 }
 
-static void read_tempreg_nb_zen(struct pci_dev *pdev, u32 *regval)
+static int read_tempreg_nb_zen(struct pci_dev *pdev, u32 *regval)
 {
-	amd_smn_read(amd_pci_dev_to_node_id(pdev),
-		     ZEN_REPORTED_TEMP_CTRL_BASE, regval);
+	return amd_smn_read(amd_pci_dev_to_node_id(pdev),
+			    ZEN_REPORTED_TEMP_CTRL_BASE, regval);
 }
 
-static long get_raw_temp(struct k10temp_data *data)
+static int get_raw_temp(struct k10temp_data *data, long *val)
 {
 	u32 regval;
-	long temp;
+	int ret;
 
-	data->read_tempreg(data->pdev, &regval);
-	temp = (regval >> ZEN_CUR_TEMP_SHIFT) * 125;
+	ret = data->read_tempreg(data->pdev, &regval);
+	if (ret)
+		return ret;
+	*val = (regval >> ZEN_CUR_TEMP_SHIFT) * 125;
 	if (regval & data->temp_adjust_mask)
-		temp -= 49000;
-	return temp;
+		*val -= 49000;
+	if (*val < 0)
+		return -EINVAL;
+	return 0;
 }
 
 static const char *k10temp_temp_label[] = {
@@ -212,24 +222,27 @@ static int k10temp_read_temp(struct device *dev, u32 attr, int channel,
 {
 	struct k10temp_data *data = dev_get_drvdata(dev);
 	u32 regval;
+	int ret;
 
 	switch (attr) {
 	case hwmon_temp_input:
 		switch (channel) {
 		case 0:		/* Tctl */
-			*val = get_raw_temp(data);
-			if (*val < 0)
-				*val = 0;
+			ret = get_raw_temp(data, val);
+			if (ret)
+				return ret;
 			break;
 		case 1:		/* Tdie */
-			*val = get_raw_temp(data) - data->temp_offset;
-			if (*val < 0)
-				*val = 0;
+			ret = get_raw_temp(data, val) - data->temp_offset;
+			if (ret)
+				return ret;
 			break;
 		case 2 ... 9:		/* Tccd{1-8} */
-			amd_smn_read(amd_pci_dev_to_node_id(data->pdev),
+			ret = amd_smn_read(amd_pci_dev_to_node_id(data->pdev),
 				     ZEN_CCD_TEMP(data->ccd_offset, channel - 2),
 						  &regval);
+			if (ret)
+				return ret;
 			*val = (regval & ZEN_CCD_TEMP_MASK) * 125 - 49000;
 			break;
 		default:
@@ -240,11 +253,15 @@ static int k10temp_read_temp(struct device *dev, u32 attr, int channel,
 		*val = 70 * 1000;
 		break;
 	case hwmon_temp_crit:
-		data->read_htcreg(data->pdev, &regval);
+		ret = data->read_htcreg(data->pdev, &regval);
+		if (ret)
+			return ret;
 		*val = ((regval >> 16) & 0x7f) * 500 + 52000;
 		break;
 	case hwmon_temp_crit_hyst:
-		data->read_htcreg(data->pdev, &regval);
+		ret = data->read_htcreg(data->pdev, &regval);
+		if (ret)
+			return ret;
 		*val = (((regval >> 16) & 0x7f)
 			- ((regval >> 24) & 0xf)) * 500 + 52000;
 		break;
-- 
2.25.1