Add OnKey support for DA9063

Add MFD support for the DA9063 OnKey driver

drivers/mfd/da9063-core.c +50 -0

@@ -60,6 +60,7 @@ static struct resource da9063_rtc_resources[] = {
 
 static struct resource da9063_onkey_resources[] = {
        {
+               .name   = "ONKEY",
                .start  = DA9063_IRQ_ONKEY,
                .end    = DA9063_IRQ_ONKEY,
                .flags  = IORESOURCE_IRQ,

@@ -97,6 +98,7 @@ static const struct mfd_cell da9063_devs[] = {
                .name           = DA9063_DRVNAME_ONKEY,
                .num_resources  = ARRAY_SIZE(da9063_onkey_resources),
                .resources      = da9063_onkey_resources,
+               .of_compatible = "dlg,da9063-onkey",
        },
        {
                .name           = DA9063_DRVNAME_RTC,

@@ -109,12 +111,64 @@ static const struct mfd_cell da9063_devs[] = {
        },
 };
 
+static int da9063_clear_fault_log(struct da9063 *da9063)
+{
+       int ret = 0;
+       int fault_log = 0;
+
+       ret = regmap_read(da9063->regmap, DA9063_REG_FAULT_LOG, &fault_log);
+       if (ret < 0) {
+               dev_err(da9063->dev, "Cannot read FAULT_LOG.\n");
+               return -EIO;
+       }
+
+       if (fault_log) {
+               if (fault_log & DA9063_TWD_ERROR)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_TWD_ERROR\n");
+               if (fault_log & DA9063_POR)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_POR\n");
+               if (fault_log & DA9063_VDD_FAULT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_VDD_FAULT\n");
+               if (fault_log & DA9063_VDD_START)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_VDD_START\n");
+               if (fault_log & DA9063_TEMP_CRIT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_TEMP_CRIT\n");
+               if (fault_log & DA9063_KEY_RESET)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_KEY_RESET\n");
+               if (fault_log & DA9063_NSHUTDOWN)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_NSHUTDOWN\n");
+               if (fault_log & DA9063_WAIT_SHUT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_WAIT_SHUT\n");
+       }
+
+       ret = regmap_write(da9063->regmap,
+                          DA9063_REG_FAULT_LOG,
+                          fault_log);
+       if (ret < 0)
+               dev_err(da9063->dev,
+                       "Cannot reset FAULT_LOG values %d\n", ret);
+
+       return ret;
+}
+
 int da9063_device_init(struct da9063 *da9063, unsigned int irq)
 {
        struct da9063_pdata *pdata = da9063->dev->platform_data;

Quoted 1 line · S Twiss

Add MFD support for the DA9063 OnKey driver

Thanks for your patch!

drivers/mfd/da9063-core.c static const struct mfd_cell da9063_devs[] = {

Quoted 6 lines

drivers/mfd/da9063-core.c +6 -0

+static int da9063_clear_fault_log(struct da9063 *da9063)
+{	
+       int ret = 0;
+       int fault_log = 0;
+
+       ret = regmap_read(da9063->regmap, DA9063_REG_FAULT_LOG,

&fault_log);

Quoted 48 lines

drivers/mfd/da9063-core.c +42 -0

+       if (ret < 0) {
+               dev_err(da9063->dev, "Cannot read FAULT_LOG.\n");
+               return -EIO;
+       }
+
+       if (fault_log) {
+               if (fault_log & DA9063_TWD_ERROR)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_TWD_ERROR\n");
+               if (fault_log & DA9063_POR)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_POR\n");
+               if (fault_log & DA9063_VDD_FAULT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_VDD_FAULT\n");
+               if (fault_log & DA9063_VDD_START)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_VDD_START\n");
+               if (fault_log & DA9063_TEMP_CRIT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_TEMP_CRIT\n");
+               if (fault_log & DA9063_KEY_RESET)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_KEY_RESET\n");
+               if (fault_log & DA9063_NSHUTDOWN)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_NSHUTDOWN\n");
+               if (fault_log & DA9063_WAIT_SHUT)
+                       dev_dbg(da9063->dev,
+                               "Fault log entry detected: DA9063_WAIT_SHUT\n");
+       }
+
+       ret = regmap_write(da9063->regmap,
+                          DA9063_REG_FAULT_LOG,
+                          fault_log);
+       if (ret < 0)
+               dev_err(da9063->dev,
+                       "Cannot reset FAULT_LOG values %d\n", ret);
+
+       return ret;
+}
+
 int da9063_device_init(struct da9063 *da9063, unsigned int irq)
 {
        struct da9063_pdata *pdata = da9063->dev->platform_data;
        int model, variant_id, variant_code;
        int ret;

drivers/mfd/da9063-core.c static const struct mfd_cell da9063_devs[] = { · line 174

Quoted 7 lines

drivers/mfd/da9063-core.c +4 -0

+       ret = da9063_clear_fault_log(da9063);
+       if (ret < 0)
+               dev_err(da9063->dev, "Cannot clear fault log\n");
+
        if (pdata) {
                da9063->flags = pdata->flags;
                da9063->irq_base = pdata->irq_base;

The code above doesn't seem to match the patch description. Can you please explain why it is needed?

Quoted 15 lines · Geert Uytterhoeven

Quoted 13 lines · S Twiss

Add MFD support for the DA9063 OnKey driver

drivers/mfd/da9063-core.c +4 -0

+static int da9063_clear_fault_log(struct da9063 *da9063)
+{
 
+}
+
 int da9063_device_init(struct da9063 *da9063, unsigned int irq)
 {
        struct da9063_pdata *pdata = da9063->dev->platform_data;
        int model, variant_id, variant_code;
        int ret;

Quoted 10 lines

drivers/mfd/da9063-core.c static const struct mfd_cell da9063_devs[] = { · line 174

Quoted 7 lines

drivers/mfd/da9063-core.c +4 -0

+       ret = da9063_clear_fault_log(da9063);
+       if (ret < 0)
+               dev_err(da9063->dev, "Cannot clear fault log\n");
+
        if (pdata) {
                da9063->flags = pdata->flags;
                da9063->irq_base = pdata->irq_base;

The code above doesn't seem to match the patch description. Can you please explain why it is needed?

Yes, at first it does seem that the fault-log clearing function is unrelated to the "MFD support for the DA9063 OnKey driver", but there is an important connection that makes it essential for the OnKey driver in this case.

I have made some explanation of the OnKey's operation in this thread here:
https://lkml.org/lkml/2015/4/29/406

But I only described the OnKey's point-of-view for case (4) of the "OnKey operation" Case (4): the long-long press and no key release -- the hardware power-cut when software is unable to respond (for whatever reason).

In this case, if the software was not responsive and a hardware shutdown of the device was chosen, the FAULT_LOG would persist with information that would be accessible when the device was restarted: it would be possible to take action the next time the device was turned on again (maybe to trigger some mitigation exercise in the bootloader -- e.g. say to complete memory checks or put the device into a safe mode).

However this mitigation exercise and clearance of the fault-log cannot be counted on outside the Linux kernel and so the clearance function da9063_clear_fault_log () has been done here.

If this clearance function did not exist, then after a hardware shutdown (due to S/W failure), the next time the device is restarted the FAULT_LOG would persist with values from the previous error.

Quoted 47 lines · Opensource [Steve Twiss]

Quoted 13 lines · Geert Uytterhoeven

Quoted 12 lines · S Twiss

Add MFD support for the DA9063 OnKey driver

drivers/mfd/da9063-core.c +4 -0

+static int da9063_clear_fault_log(struct da9063 *da9063)
+{
 
+}
+
 int da9063_device_init(struct da9063 *da9063, unsigned int irq)
 {
        struct da9063_pdata *pdata = da9063->dev->platform_data;
        int model, variant_id, variant_code;
        int ret;

Quoted 10 lines

drivers/mfd/da9063-core.c static const struct mfd_cell da9063_devs[] = { · line 174

Quoted 7 lines

drivers/mfd/da9063-core.c +4 -0

+       ret = da9063_clear_fault_log(da9063);
+       if (ret < 0)
+               dev_err(da9063->dev, "Cannot clear fault log\n");
+
        if (pdata) {
                da9063->flags = pdata->flags;
                da9063->irq_base = pdata->irq_base;

The code above doesn't seem to match the patch description. Can you please explain why it is needed?

Yes, at first it does seem that the fault-log clearing function is unrelated to the "MFD support for the DA9063 OnKey driver", but there is an important connection that makes it essential for the OnKey driver in this case.

I have made some explanation of the OnKey's operation in this thread here:
https://lkml.org/lkml/2015/4/29/406

But I only described the OnKey's point-of-view for case (4) of the "OnKey operation" Case (4): the long-long press and no key release -- the hardware power-cut when software is unable to respond (for whatever reason).

In this case, if the software was not responsive and a hardware shutdown of the device was chosen, the FAULT_LOG would persist with information that would be accessible when the device was restarted: it would be possible to take action the next time the device was turned on again (maybe to trigger some mitigation exercise in the bootloader -- e.g. say to complete memory checks or put the device into a safe mode).

However this mitigation exercise and clearance of the fault-log cannot be counted on outside the Linux kernel and so the clearance function da9063_clear_fault_log () has been done here.

Quoted 3 lines

If this clearance function did not exist, then after a hardware shutdown (due to S/W failure), the next time the device is restarted the FAULT_LOG would persist with values from the previous error.

Thanks for your explanation!

Please add (some parts of it) to the patch description.