mvebu: puzzle-mcu: improve led driver

Set blinking mode using scheduled work instead of blocking which may
result in deadlocks.
Add dynamic kprintf debugging hexdumps of all MCU rx and tx.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
(cherry picked from commit 7e4c1cca8a137ca4fe5132b8c058e52ba82defac)

diff --git a/target/linux/mvebu/patches-5.4/910-drivers-leds-wt61p803-puzzle-improvements.patch b/target/linux/mvebu/patches-5.4/910-drivers-leds-wt61p803-puzzle-improvements.patch
index 1e065ed6e77ce03c0f66d86161d2ad00b7df36b0..150a65498cd3d407dd6e29acb411a08d66d695a1 100644 (file)
--- a/target/linux/mvebu/patches-5.4/910-drivers-leds-wt61p803-puzzle-improvements.patch
+++ b/target/linux/mvebu/patches-5.4/910-drivers-leds-wt61p803-puzzle-improvements.patch
@@ -1,6 +1,6 @@
 --- a/drivers/leds/leds-iei-wt61p803-puzzle.c
 +++ b/drivers/leds/leds-iei-wt61p803-puzzle.c
-@@ -9,10 +9,13 @@
+@@ -9,9 +9,13 @@
  #include <linux/mfd/iei-wt61p803-puzzle.h>
  #include <linux/mod_devicetable.h>
  #include <linux/module.h>
@@ -8,34 +8,34 @@
  #include <linux/platform_device.h>
  #include <linux/property.h>
  #include <linux/slab.h>
- 
-+#define IEI_LEDS_MAX          4
++#include <linux/workqueue.h>
 +
++#define IEI_LEDS_MAX          4
+ 
  enum iei_wt61p803_puzzle_led_state {
        IEI_LED_OFF = 0x30,
-       IEI_LED_ON = 0x31,
-@@ -34,6 +37,9 @@ struct iei_wt61p803_puzzle_led {
+@@ -33,7 +37,11 @@ struct iei_wt61p803_puzzle_led {
+       struct iei_wt61p803_puzzle *mcu;
        unsigned char response_buffer[IEI_WT61P803_PUZZLE_BUF_SIZE];
        struct mutex lock; /* mutex to protect led_power_state */
++      struct work_struct work;
        int led_power_state;
 +      int id;
-+      bool blinking;
++      u8 blinking;
 +      bool active_low;
  };
  
  static inline struct iei_wt61p803_puzzle_led *cdev_to_iei_wt61p803_puzzle_led
-@@ -51,10 +57,20 @@ static int iei_wt61p803_puzzle_led_brigh
+@@ -51,10 +59,18 @@ static int iei_wt61p803_puzzle_led_brigh
        size_t reply_size;
        int ret;
  
-+      mutex_lock(&priv->lock);
 +      if (priv->blinking) {
 +              if (brightness == LED_OFF)
-+                      priv->blinking = false;
++                      priv->blinking = 0;
 +              else
 +                      return 0;
 +      }
-+      mutex_unlock(&priv->lock);
 +
        led_power_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
        led_power_cmd[1] = IEI_WT61P803_PUZZLE_CMD_LED;
@@ -43,22 +43,40 @@
 -      led_power_cmd[3] = brightness == LED_OFF ? IEI_LED_OFF : IEI_LED_ON;
 +      led_power_cmd[2] = IEI_WT61P803_PUZZLE_CMD_LED_SET(priv->id);
 +      led_power_cmd[3] = ((brightness == LED_OFF) ^ priv->active_low) ?
-+                              IEI_LED_OFF : IEI_LED_ON;
++                              IEI_LED_OFF : priv->blinking?priv->blinking:IEI_LED_ON;
  
        ret = iei_wt61p803_puzzle_write_command(priv->mcu, led_power_cmd,
                                                sizeof(led_power_cmd),
-@@ -90,39 +106,164 @@ static enum led_brightness iei_wt61p803_
+@@ -90,39 +106,166 @@ static enum led_brightness iei_wt61p803_
        return led_state;
  }
  
++static void iei_wt61p803_puzzle_led_apply_blink(struct work_struct *work)
++{
++      struct iei_wt61p803_puzzle_led *priv = container_of(work, struct iei_wt61p803_puzzle_led, work);
++      unsigned char led_blink_cmd[5] = {};
++      unsigned char resp_buf[IEI_WT61P803_PUZZLE_BUF_SIZE];
++      size_t reply_size;
++
++      led_blink_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
++      led_blink_cmd[1] = IEI_WT61P803_PUZZLE_CMD_LED;
++      led_blink_cmd[2] = IEI_WT61P803_PUZZLE_CMD_LED_SET(priv->id);
++      led_blink_cmd[3] = priv->blinking;
++
++      iei_wt61p803_puzzle_write_command(priv->mcu, led_blink_cmd,
++                                        sizeof(led_blink_cmd),
++                                        resp_buf,
++                                        &reply_size);
++
++      return;
++}
++
 +static int iei_wt61p803_puzzle_led_set_blink(struct led_classdev *cdev,
 +                                           unsigned long *delay_on,
 +                                           unsigned long *delay_off)
 +{
 +      struct iei_wt61p803_puzzle_led *priv = cdev_to_iei_wt61p803_puzzle_led(cdev);
-+      unsigned char led_blink_cmd[5] = {};
-+      unsigned char resp_buf[IEI_WT61P803_PUZZLE_BUF_SIZE];
-+      size_t reply_size;
++      u8 blink_mode = 0;
 +      int ret = 0;
 +
 +      /* set defaults */
@@ -67,57 +85,39 @@
 +              *delay_off = 500;
 +      }
 +
-+      /* minimum delay for soft-driven blinking is 50ms to keep load low */
-+      if (*delay_on < 50)
-+              *delay_on = 50;
-+
-+      if (*delay_off < 50)
-+              *delay_off = 50;
++      /* minimum delay for soft-driven blinking is 100ms to keep load low */
++      if (*delay_on < 100)
++              *delay_on = 100;
 +
-+      if (*delay_on != *delay_off)
-+              return -EINVAL;
++      if (*delay_off < 100)
++              *delay_off = 100;
 +
-+      /* aggressively offload blinking to hardware, if possible */
-+      if (*delay_on < 100) {
-+              return -EINVAL;
-+      } else if (*delay_on < 200) {
++      /* offload blinking to hardware, if possible */
++      if (*delay_on != *delay_off) {
++              ret = -EINVAL;
++      } else if (*delay_on == 100) {
++              blink_mode = IEI_LED_BLINK_5HZ;
 +              *delay_on = 100;
 +              *delay_off = 100;
 +      } else if (*delay_on <= 500) {
++              blink_mode = IEI_LED_BLINK_1HZ;
 +              *delay_on = 500;
 +              *delay_off = 500;
 +      } else {
-+              return -EINVAL;
++              ret = -EINVAL;
 +      }
 +
-+      led_blink_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
-+      led_blink_cmd[1] = IEI_WT61P803_PUZZLE_CMD_LED;
-+      led_blink_cmd[2] = IEI_WT61P803_PUZZLE_CMD_LED_SET(priv->id);
-+      led_blink_cmd[3] = (*delay_on == 100)?IEI_LED_BLINK_5HZ:IEI_LED_BLINK_1HZ;
-+
-+      ret = iei_wt61p803_puzzle_write_command(priv->mcu, led_blink_cmd,
-+                                              sizeof(led_blink_cmd),
-+                                              resp_buf,
-+                                              &reply_size);
-+
-+      if (ret)
-+              return ret;
-+
-+      if (reply_size != 3)
-+              return -EIO;
-+
-+      if (!(resp_buf[0] == IEI_WT61P803_PUZZLE_CMD_HEADER_START &&
-+            resp_buf[1] == IEI_WT61P803_PUZZLE_CMD_RESPONSE_OK &&
-+            resp_buf[2] == IEI_WT61P803_PUZZLE_CHECKSUM_RESPONSE_OK))
-+              return -EIO;
-+
 +      mutex_lock(&priv->lock);
-+      priv->blinking = true;
++      priv->blinking = blink_mode;
 +      mutex_unlock(&priv->lock);
 +
++      if (blink_mode)
++              schedule_work(&priv->work);
++
 +      return ret;
 +}
 +
++
 +static int iei_wt61p803_puzzle_led_set_dt_default(struct led_classdev *cdev,
 +                                   struct device_node *np)
 +{
@@ -204,7 +204,7 @@
 +              priv->mcu = mcu;
 +              priv->id = reg;
 +              priv->led_power_state = 1;
-+              priv->blinking = false;
++              priv->blinking = 0;
 +              init_data.fwnode = of_fwnode_handle(child);
 +
 +              priv->cdev.brightness_set_blocking = iei_wt61p803_puzzle_led_brightness_set_blocking;
@@ -213,6 +213,8 @@
 +
 +              priv->cdev.max_brightness = 1;
 +
++              INIT_WORK(&priv->work, iei_wt61p803_puzzle_led_apply_blink);
++
 +              ret = iei_wt61p803_puzzle_led_set_dt_default(&priv->cdev, child);
 +              if (ret) {
 +                      dev_err(dev, "Could apply default from DT\n");
@@ -245,3 +247,25 @@
  
  #define IEI_WT61P803_PUZZLE_CMD_TEMP                  0x54 /* T */
  #define IEI_WT61P803_PUZZLE_CMD_TEMP_ALL              0x41 /* A */
+--- a/drivers/mfd/iei-wt61p803-puzzle.c
++++ b/drivers/mfd/iei-wt61p803-puzzle.c
+@@ -176,6 +176,9 @@ static int iei_wt61p803_puzzle_recv_buf(
+       struct iei_wt61p803_puzzle *mcu = serdev_device_get_drvdata(serdev);
+       int ret;
+ 
++      print_hex_dump_debug("puzzle-mcu rx: ", DUMP_PREFIX_NONE,
++                           16, 1, data, size, false);
++
+       ret = iei_wt61p803_puzzle_process_resp(mcu, data, size);
+       /* Return the number of processed bytes if function returns error,
+        * discard the remaining incoming data, since the frame this data
+@@ -246,6 +249,9 @@ int iei_wt61p803_puzzle_write_command(st
+ 
+       cmd[size - 1] = iei_wt61p803_puzzle_checksum(cmd, size - 1);
+ 
++      print_hex_dump_debug("puzzle-mcu tx: ", DUMP_PREFIX_NONE,
++                           16, 1, cmd, size, false);
++
+       /* Initialize reply struct */
+       reinit_completion(&mcu->reply->received);
+       mcu->reply->size = 0;