hw/i2c: pmbus: add fan support

PMBus devices may integrate fans whose operation is configurable
over PMBus. This commit allows the driver to read and write the
fan control registers but does not model the operation of fans.

Reviewed-by: Stephen Longfield <slongfield@google.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Titus Rwantare <titusr@google.com>
Message-ID: <20231023-staging-pmbus-v3-v4-3-07a8cb7cd20a@google.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

2 files changed, 177 insertions, 0 deletions

diff --git a/hw/i2c/pmbus_device.c b/hw/i2c/pmbus_device.c
index ea15490720..c1d8c93056 100644
--- a/hw/i2c/pmbus_device.c
+++ b/hw/i2c/pmbus_device.c
@@ -500,6 +500,54 @@ static uint8_t pmbus_receive_byte(SMBusDevice *smd)
         }
         break;
 
+    case PMBUS_FAN_CONFIG_1_2:            /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].fan_config_1_2);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_1:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].fan_command_1);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_2:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].fan_command_2);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_FAN_CONFIG_3_4:            /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].fan_config_3_4);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_3:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].fan_command_3);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_4:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].fan_command_4);
+        } else {
+            goto passthough;
+        }
+        break;
+
     case PMBUS_VOUT_OV_FAULT_LIMIT:       /* R/W word */
         if (pmdev->pages[index].page_flags & PB_HAS_VOUT) {
             pmbus_send16(pmdev, pmdev->pages[index].vout_ov_fault_limit);
@@ -810,6 +858,22 @@ static uint8_t pmbus_receive_byte(SMBusDevice *smd)
         pmbus_send8(pmdev, pmdev->pages[index].status_mfr_specific);
         break;
 
+    case PMBUS_STATUS_FANS_1_2:           /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].status_fans_1_2);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_STATUS_FANS_3_4:           /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].status_fans_3_4);
+        } else {
+            goto passthough;
+        }
+        break;
+
     case PMBUS_READ_EIN:                  /* Read-Only block 5 bytes */
         if (pmdev->pages[index].page_flags & PB_HAS_EIN) {
             pmbus_send(pmdev, pmdev->pages[index].read_ein, 5);
@@ -882,6 +946,54 @@ static uint8_t pmbus_receive_byte(SMBusDevice *smd)
         }
         break;
 
+    case PMBUS_READ_FAN_SPEED_1:          /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_fan_speed_1);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_READ_FAN_SPEED_2:          /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_fan_speed_2);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_READ_FAN_SPEED_3:          /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_fan_speed_3);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_READ_FAN_SPEED_4:          /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_fan_speed_4);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_READ_DUTY_CYCLE:           /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_duty_cycle);
+        } else {
+            goto passthough;
+        }
+        break;
+
+    case PMBUS_READ_FREQUENCY:            /* Read-Only word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send16(pmdev, pmdev->pages[index].read_frequency);
+        } else {
+            goto passthough;
+        }
+        break;
+
     case PMBUS_READ_POUT:                 /* Read-Only word */
         if (pmdev->pages[index].page_flags & PB_HAS_POUT) {
             pmbus_send16(pmdev, pmdev->pages[index].read_pout);
@@ -1305,6 +1417,54 @@ static int pmbus_write_data(SMBusDevice *smd, uint8_t *buf, uint8_t len)
         }
         break;
 
+    case PMBUS_FAN_CONFIG_1_2:            /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_config_1_2 = pmbus_receive8(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_1:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_command_1 = pmbus_receive16(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_2:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_command_2 = pmbus_receive16(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_FAN_CONFIG_3_4:            /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_config_3_4 = pmbus_receive8(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_3:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_command_3 = pmbus_receive16(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_FAN_COMMAND_4:             /* R/W word */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmdev->pages[index].fan_command_4 = pmbus_receive16(pmdev);
+        } else {
+            goto passthrough;
+        }
+        break;
+
     case PMBUS_VOUT_OV_FAULT_LIMIT:       /* R/W word */
         if (pmdev->pages[index].page_flags & PB_HAS_VOUT) {
             pmdev->pages[index].vout_ov_fault_limit = pmbus_receive16(pmdev);
@@ -1610,6 +1770,22 @@ static int pmbus_write_data(SMBusDevice *smd, uint8_t *buf, uint8_t len)
         pmdev->pages[index].status_mfr_specific = pmbus_receive8(pmdev);
         break;
 
+    case PMBUS_STATUS_FANS_1_2:           /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].status_fans_1_2);
+        } else {
+            goto passthrough;
+        }
+        break;
+
+    case PMBUS_STATUS_FANS_3_4:           /* R/W byte */
+        if (pmdev->pages[index].page_flags & PB_HAS_FAN) {
+            pmbus_send8(pmdev, pmdev->pages[index].status_fans_3_4);
+        } else {
+            goto passthrough;
+        }
+        break;
+
     case PMBUS_PAGE_PLUS_READ:            /* Block Read-only */
     case PMBUS_CAPABILITY:                /* Read-Only byte */
     case PMBUS_COEFFICIENTS:              /* Read-only block 5 bytes */
diff --git a/include/hw/i2c/pmbus_device.h b/include/hw/i2c/pmbus_device.h
index 2e95164aa1..ad431bdc7c 100644
--- a/include/hw/i2c/pmbus_device.h
+++ b/include/hw/i2c/pmbus_device.h
@@ -258,6 +258,7 @@ OBJECT_DECLARE_TYPE(PMBusDevice, PMBusDeviceClass,
 #define PB_HAS_TEMP2               BIT_ULL(41)
 #define PB_HAS_TEMP3               BIT_ULL(42)
 #define PB_HAS_TEMP_RATING         BIT_ULL(43)
+#define PB_HAS_FAN                 BIT_ULL(44)
 #define PB_HAS_MFR_INFO            BIT_ULL(50)
 #define PB_HAS_STATUS_MFR_SPECIFIC BIT_ULL(51)