[PATCH-v4 1/3] mfd: 88pm800: Add device tree support

[yizhang@marvell.com (Yi Zhang)]

On Fri, Jun 26, 2015 at 11:29:29AM +0530, Vaibhav Hiremath wrote:
> 
> 
> On Friday 26 June 2015 11:23 AM, Yi Zhang wrote:
> >On Thu, Jun 25, 2015 at 08:57:49PM +0530, Vaibhav Hiremath wrote:
> >>
> >>
> >>On Thursday 25 June 2015 08:18 PM, Lee Jones wrote:
> >>>On Thu, 25 Jun 2015, Vaibhav Hiremath wrote:
> >>>>On Thursday 25 June 2015 03:49 PM, Lee Jones wrote:
> >>>>>On Thu, 25 Jun 2015, Vaibhav Hiremath wrote:
> >>>>>
> >>>>>>Add DT support to the 88pm800 driver, along with compatible
> >>>>>>field for it's sub-devices (rtc, onkey and regulator)
> >>>>>>
> >>>>>>Signed-off-by: Chao Xie <chao.xie@marvell.com>
> >>>>>>Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
> >>>>>>---
> >>>>>>  drivers/mfd/88pm800.c | 23 +++++++++++++++++++++++
> >>>>>>  1 file changed, 23 insertions(+)
> >>>>>>
> >>>>>>diff --git a/drivers/mfd/88pm800.c b/drivers/mfd/88pm800.c
> >>>>>>index 841717a..40fd014 100644
> >>>>>>--- a/drivers/mfd/88pm800.c
> >>>>>>+++ b/drivers/mfd/88pm800.c
> >>>>>>@@ -27,6 +27,7 @@
> >>>>>>  #include <linux/mfd/core.h>
> >>>>>>  #include <linux/mfd/88pm80x.h>
> >>>>>>  #include <linux/slab.h>
> >>>>>>+#include <linux/of_device.h>
> >>>>>>
> >>>>>>  /* Interrupt Registers */
> >>>>>>  #define PM800_INT_STATUS1		(0x05)
> >>>>>>@@ -121,6 +122,11 @@ static const struct i2c_device_id pm80x_id_table[] = {
> >>>>>>  };
> >>>>>>  MODULE_DEVICE_TABLE(i2c, pm80x_id_table);
> >>>>>>
> >>>>>>+static const struct of_device_id pm80x_of_match_table[] = {
> >>>>>>+	{ .compatible = "marvell,88pm800", },
> >>>>>>+	{},
> >>>>>>+};
> >>>>>>+
> >>>>>>  static struct resource rtc_resources[] = {
> >>>>>>  	{
> >>>>>>  	 .name = "88pm80x-rtc",
> >>>>>>@@ -133,6 +139,7 @@ static struct resource rtc_resources[] = {
> >>>>>>  static struct mfd_cell rtc_devs[] = {
> >>>>>>  	{
> >>>>>>  	 .name = "88pm80x-rtc",
> >>>>>>+	 .of_compatible = "marvell,88pm80x-rtc",
> >>>>>>  	 .num_resources = ARRAY_SIZE(rtc_resources),
> >>>>>>  	 .resources = &rtc_resources[0],
> >>>>>>  	 .id = -1,
> >>>>>>@@ -151,6 +158,7 @@ static struct resource onkey_resources[] = {
> >>>>>>  static const struct mfd_cell onkey_devs[] = {
> >>>>>>  	{
> >>>>>>  	 .name = "88pm80x-onkey",
> >>>>>>+	 .of_compatible = "marvell,88pm80x-onkey",
> >>>>>>  	 .num_resources = 1,
> >>>>>>  	 .resources = &onkey_resources[0],
> >>>>>>  	 .id = -1,
> >>>>>>@@ -160,6 +168,7 @@ static const struct mfd_cell onkey_devs[] = {
> >>>>>>  static const struct mfd_cell regulator_devs[] = {
> >>>>>>  	{
> >>>>>>  	 .name = "88pm80x-regulator",
> >>>>>>+	 .of_compatible = "marvell,88pm80x-regulator",
> >>>>>>  	 .id = -1,
> >>>>>>  	},
> >>>>>>  };
> >>>>>>@@ -544,8 +553,21 @@ static int pm800_probe(struct i2c_client *client,
> >>>>>>  	int ret = 0;
> >>>>>>  	struct pm80x_chip *chip;
> >>>>>>  	struct pm80x_platform_data *pdata = dev_get_platdata(&client->dev);
> >>>>>>+	struct device_node *np = client->dev.of_node;
> >>>>>>  	struct pm80x_subchip *subchip;
> >>>>>>
> >>>>>>+	if (!pdata && !np) {
> >>>>>>+		dev_err(&client->dev,
> >>>>>>+			"pm80x requires platform data or of_node\n");
> >>>>>>+		return -EINVAL;
> >>>>>>+	}
> >>>>>>+
> >>>>>>+	if (!pdata) {
> >>>>>>+		pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
> >>>>>>+		if (!pdata)
> >>>>>>+			return -ENOMEM;
> >>>>>>+	}
> >>>>>
> >>>>>Why have you allocated data for pdata, then done nothing with it?
> >>>>>
> >>>>
> >>>>Not in this patch, but subsequent patches would use it.
> >>>
> >>>Only provide it when you start using it please.
> >>>
> >>
> >>I will take back my earlier comment of "not using in this patch, but
> >>subsequent patches".
> >>
> >>pdata is being used, couple of places in the driver,
> >>
> >>
> >>@line-751
> >>
> >>         ret = device_800_init(chip, pdata);
> >>         if (ret) {
> >>                 dev_err(chip->dev, "Failed to initialize 88pm800
> >>devices\n");
> >>                 goto err_device_init;
> >>         }
> >>
> >>         if (pdata && pdata->plat_config)
> >>                 pdata->plat_config(chip, pdata);
> >
> >   this plat_config() is used in legacy non-device-tree code, it's used
> >   to implement fixup for chip or board level, it exists in
> >   the board configuration file
> >
> >   just curious, do you think we still need to keep it?
> >   considering device-tree has been used. thanks;
> >
> 
> I do not see it anywhere in mainline kernel tree, is it part of some
> internal tree?
> 
> If we know that it is being used, then lets not remove it now.

  Yes, got your point, it may still be used by other trees, thanks;
> 
> Thanks,
> Vaibhav