[PATCH v8 1/2] powerpc/rtas: Rename rtas_error_rc to rtas_generic_errno

[Mahesh Salgaonkar <mahesh@xxxxxxxxxxxxx>]

rtas_generic_errno() function will convert the generic rtas return codes
into errno. Also, #define descriptive names for rtas return codes and use
it instead of numeric values.

Signed-off-by: Mahesh Salgaonkar <mahesh@xxxxxxxxxxxxx>
---

(no changes since v7)

Change in V7:
- Until v6 there was only one patch with subject "PCI hotplug: rpaphp:
  Error out on busy status from get-sensor-state". Starting from v7, adding
  this new patch to introduce rtas_generic_errno() to handle generic rtas
  error codes.
  https://lore.kernel.org/all/20220429162545.GA79541@bhelgaas/
---
 arch/powerpc/include/asm/rtas.h |   10 +++++++
 arch/powerpc/kernel/rtas.c      |   53 ++++++++++++++++++++-------------------
 2 files changed, 36 insertions(+), 27 deletions(-)

diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index 3abe15ac79db1..5572a0a2f6e18 100644
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -202,7 +202,9 @@ typedef struct {
 #define RTAS_USER_REGION_SIZE (64 * 1024)
 
 /* RTAS return status codes */
-#define RTAS_BUSY		-2    /* RTAS Busy */
+#define RTAS_HARDWARE_ERROR	(-1)  /* Hardware Error */
+#define RTAS_BUSY		(-2)  /* RTAS Busy */
+#define RTAS_INVALID_PARAMETER	(-3)  /* Invalid indicator/domain/sensor etc. */
 #define RTAS_EXTENDED_DELAY_MIN	9900
 #define RTAS_EXTENDED_DELAY_MAX	9905
 
@@ -212,6 +214,11 @@ typedef struct {
 #define RTAS_THREADS_ACTIVE     -9005 /* Multiple processor threads active */
 #define RTAS_OUTSTANDING_COPROC -9006 /* Outstanding coprocessor operations */
 
+/* statuses specific to get-sensor-state */
+#define RTAS_SLOT_UNISOLATED		(-9000)
+#define RTAS_SLOT_NOT_UNISOLATED	(-9001)
+#define RTAS_SLOT_NOT_USABLE		(-9002)
+
 /* RTAS event classes */
 #define RTAS_INTERNAL_ERROR		0x80000000 /* set bit 0 */
 #define RTAS_EPOW_WARNING		0x40000000 /* set bit 1 */
@@ -425,6 +432,7 @@ extern int rtas_set_indicator(int indicator, int index, int new_value);
 extern int rtas_set_indicator_fast(int indicator, int index, int new_value);
 extern void rtas_progress(char *s, unsigned short hex);
 int rtas_ibm_suspend_me(int *fw_status);
+int rtas_generic_errno(int rtas_rc);
 
 struct rtc_time;
 extern time64_t rtas_get_boot_time(void);
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index c087eeee320ff..80b6099e8ce20 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -1330,33 +1330,34 @@ bool __ref rtas_busy_delay(int status)
 }
 EXPORT_SYMBOL_GPL(rtas_busy_delay);
 
-static int rtas_error_rc(int rtas_rc)
+int rtas_generic_errno(int rtas_rc)
 {
 	int rc;
 
 	switch (rtas_rc) {
-		case -1: 		/* Hardware Error */
-			rc = -EIO;
-			break;
-		case -3:		/* Bad indicator/domain/etc */
-			rc = -EINVAL;
-			break;
-		case -9000:		/* Isolation error */
-			rc = -EFAULT;
-			break;
-		case -9001:		/* Outstanding TCE/PTE */
-			rc = -EEXIST;
-			break;
-		case -9002:		/* No usable slot */
-			rc = -ENODEV;
-			break;
-		default:
-			pr_err("%s: unexpected error %d\n", __func__, rtas_rc);
-			rc = -ERANGE;
-			break;
+	case RTAS_HARDWARE_ERROR:	/* Hardware Error */
+		rc = -EIO;
+		break;
+	case RTAS_INVALID_PARAMETER:	/* Bad indicator/domain/etc */
+		rc = -EINVAL;
+		break;
+	case RTAS_SLOT_UNISOLATED:	/* Isolation error */
+		rc = -EFAULT;
+		break;
+	case RTAS_SLOT_NOT_UNISOLATED:	/* Outstanding TCE/PTE */
+		rc = -EEXIST;
+		break;
+	case RTAS_SLOT_NOT_USABLE:	/* No usable slot */
+		rc = -ENODEV;
+		break;
+	default:
+		pr_err("%s: unexpected error %d\n", __func__, rtas_rc);
+		rc = -ERANGE;
+		break;
 	}
 	return rc;
 }
+EXPORT_SYMBOL(rtas_generic_errno);
 
 int rtas_get_power_level(int powerdomain, int *level)
 {
@@ -1370,7 +1371,7 @@ int rtas_get_power_level(int powerdomain, int *level)
 		udelay(1);
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(rtas_get_power_level);
@@ -1388,7 +1389,7 @@ int rtas_set_power_level(int powerdomain, int level, int *setlevel)
 	} while (rtas_busy_delay(rc));
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(rtas_set_power_level);
@@ -1406,7 +1407,7 @@ int rtas_get_sensor(int sensor, int index, int *state)
 	} while (rtas_busy_delay(rc));
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(rtas_get_sensor);
@@ -1424,7 +1425,7 @@ int rtas_get_sensor_fast(int sensor, int index, int *state)
 				    rc <= RTAS_EXTENDED_DELAY_MAX));
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 	return rc;
 }
 
@@ -1466,7 +1467,7 @@ int rtas_set_indicator(int indicator, int index, int new_value)
 	} while (rtas_busy_delay(rc));
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(rtas_set_indicator);
@@ -1488,7 +1489,7 @@ int rtas_set_indicator_fast(int indicator, int index, int new_value)
 				    rc <= RTAS_EXTENDED_DELAY_MAX));
 
 	if (rc < 0)
-		return rtas_error_rc(rc);
+		return rtas_generic_errno(rc);
 
 	return rc;
 }