Re: [PATCH v6 2/5] mfd: lm3533: Support initialization from Device Tree

From: Lee Jones
Date: Wed Feb 08 2017 - 05:44:55 EST


On Mon, 30 Jan 2017, Bjorn Andersson wrote:

> From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx>
>
> Implement support for initialization of the lm3533 driver core and
> probing child devices from Device Tree.
>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> ---
> drivers/mfd/lm3533-core.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 82 insertions(+)
>
> Note that this patch can be merged independently of the other patches in the
> series.
>
> Changes since v5:
> - Added comment re of_platform_populate()
>
> Changes since v4:
> - Moved of_node check into lm3533_pdata_from_of_node()
>
> Changes since v3:
> - Moved parsing of child of nodes into each child driver
> - Use of_platform_populate() to instanciate child devices
>
>
> diff --git a/drivers/mfd/lm3533-core.c b/drivers/mfd/lm3533-core.c
> index 5abcbb2e8849..89c79328c78e 100644
> --- a/drivers/mfd/lm3533-core.c
> +++ b/drivers/mfd/lm3533-core.c
> @@ -18,6 +18,8 @@
> #include <linux/gpio.h>
> #include <linux/i2c.h>
> #include <linux/mfd/core.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_platform.h>
> #include <linux/regmap.h>
> #include <linux/seq_file.h>
> #include <linux/slab.h>
> @@ -512,6 +514,16 @@ static int lm3533_device_init(struct lm3533 *lm3533)
> lm3533_device_bl_init(lm3533);
> lm3533_device_led_init(lm3533);
>
> + /*
> + * Check of_node as of_platform_populate treats NULL as the root node,
> + * which would cause side effects in certain unlikely DT/non-DT hybrid
> + * solutions.
> + */
> + if (lm3533->dev->of_node) {
> + of_platform_populate(lm3533->dev->of_node, NULL, NULL,
> + lm3533->dev);
> + }
> +
> ret = sysfs_create_group(&lm3533->dev->kobj, &lm3533_attribute_group);
> if (ret < 0) {
> dev_err(lm3533->dev, "failed to create sysfs attributes\n");
> @@ -588,10 +600,76 @@ static const struct regmap_config regmap_config = {
> .precious_reg = lm3533_precious_register,
> };
>
> +static int lm3533_of_parse_enum(struct device *dev, const char *propname,
> + const unsigned int *match, size_t num_matches)
> +{
> + size_t i;
> + int ret;
> + u32 val;
> +
> + ret = of_property_read_u32(dev->of_node, propname, &val);
> + if (ret < 0) {

If you do a fix-up of this driver please:

s/(ret < 0)/(ret)/

If not, it's not enough of an issue for non-acceptance:

For my own reference:
Acked-for-MFD-by: Lee Jones <lee.jones@xxxxxxxxxx>

> + dev_err(dev, "failed to parse %s\n", propname);
> + return ret;
> + }
> +
> + for (i = 0; i < num_matches; i++) {
> + if (val == match[i])
> + return i;
> + }
> +
> + dev_err(dev, "unsupported value of %s\n", propname);
> + return -EINVAL;
> +}
> +
> +static int lm3533_pdata_from_of_node(struct device *dev)
> +{
> + struct lm3533_platform_data *pdata;
> + int ret;
> + const unsigned int freqs[] = {
> + [LM3533_BOOST_FREQ_500KHZ] = 500000,
> + [LM3533_BOOST_FREQ_1000KHZ] = 1000000,
> + };
> + const unsigned int ovps[] = {
> + [LM3533_BOOST_OVP_16V] = 16000,
> + [LM3533_BOOST_OVP_24V] = 24000,
> + [LM3533_BOOST_OVP_32V] = 32000,
> + [LM3533_BOOST_OVP_40V] = 40000,
> + };
> +
> + if (!dev->of_node)
> + return 0;
> +
> + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + return -ENOMEM;
> +
> + pdata->gpio_hwen = of_get_named_gpio(dev->of_node, "hwen-gpios", 0);
> + if (pdata->gpio_hwen < 0)
> + return pdata->gpio_hwen;
> +
> + ret = lm3533_of_parse_enum(dev, "ti,boost-freq-hz",
> + freqs, ARRAY_SIZE(freqs));
> + if (ret < 0)
> + return ret;
> + pdata->boost_freq = ret;
> +
> + ret = lm3533_of_parse_enum(dev, "ti,boost-ovp-mv",
> + ovps, ARRAY_SIZE(ovps));
> + if (ret < 0)
> + return ret;
> + pdata->boost_ovp = ret;
> +
> + dev->platform_data = pdata;
> +
> + return 0;
> +}
> +
> static int lm3533_i2c_probe(struct i2c_client *i2c,
> const struct i2c_device_id *id)
> {
> struct lm3533 *lm3533;
> + int ret;
>
> dev_dbg(&i2c->dev, "%s\n", __func__);
>
> @@ -608,6 +686,10 @@ static int lm3533_i2c_probe(struct i2c_client *i2c,
> lm3533->dev = &i2c->dev;
> lm3533->irq = i2c->irq;
>
> + ret = lm3533_pdata_from_of_node(lm3533->dev);
> + if (ret < 0)
> + return ret;
> +
> return lm3533_device_init(lm3533);
> }
>

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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