[PATCH v1 06/11] ti948: Reconfigure in the alive check when device returns

[Michael Drake]

If the alive check detects a transition to the alive state,
the device configuration is rewritten.

Signed-off-by: Michael Drake <michael.dr...@codethink.co.uk>
Cc: Patrick Glaser <pgla...@tesla.com>
Cc: Nate Case <nc...@tesla.com>
---
 drivers/gpu/drm/bridge/ti948.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/ti948.c b/drivers/gpu/drm/bridge/ti948.c
index 86daa3701b91..b5c766711c4b 100644
--- a/drivers/gpu/drm/bridge/ti948.c
+++ b/drivers/gpu/drm/bridge/ti948.c
@@ -132,6 +132,8 @@ struct ti948_reg_val {
  * @reg_names:   Array of regulator names, or NULL.
  * @regs:        Array of regulators, or NULL.
  * @reg_count:   Number of entries in reg_names and regs arrays.
+ * @alive_check: Context for the alive checking work item.
+ * @alive:       Whether the device is alive or not (alive_check).
  */
 struct ti948_ctx {
        struct i2c_client *i2c;
@@ -141,6 +143,8 @@ struct ti948_ctx {
        const char **reg_names;
        struct regulator **regs;
        size_t reg_count;
+       struct delayed_work alive_check;
+       bool alive;
 };
 
 static bool ti948_readable_reg(struct device *dev, unsigned int reg)
@@ -346,6 +350,8 @@ static int ti948_power_on(struct ti948_ctx *ti948)
        if (ret != 0)
                return ret;
 
+       ti948->alive = true;
+
        msleep(500);
 
        return 0;
@@ -356,6 +362,8 @@ static int ti948_power_off(struct ti948_ctx *ti948)
        int i;
        int ret;
 
+       ti948->alive = false;
+
        for (i = ti948->reg_count; i > 0; i--) {
                dev_info(&ti948->i2c->dev, "Disabling %s regulator\n",
                                ti948->reg_names[i - 1]);
@@ -388,8 +396,17 @@ static void ti948_alive_check(struct work_struct *work)
 {
        struct delayed_work *dwork = to_delayed_work(work);
        struct ti948_ctx *ti948 = delayed_work_to_ti948_ctx(dwork);
+       int ret = ti948_device_check(ti948);
 
-       dev_info(&ti948->i2c->dev, "%s Alive check!\n", __func__);
+       if (ti948->alive == false && ret == 0) {
+               dev_info(&ti948->i2c->dev, "Device has come back to life!\n");
+               ti948_write_config_seq(ti948);
+               ti948->alive = true;
+
+       } else if (ti948->alive == true && ret != 0) {
+               dev_info(&ti948->i2c->dev, "Device has stopped responding\n");
+               ti948->alive = false;
+       }
 
        /* Reschedule ourself for the next check. */
        schedule_delayed_work(&ti948->alive_check, TI948_ALIVE_CHECK_DELAY);
-- 
2.20.1