From 9f946099fe1927aa746892232c4421e1ae175699 Mon Sep 17 00:00:00 2001 From: Richard Fitzgerald Date: Wed, 19 Nov 2014 14:13:06 +0000 Subject: regulator: gpio: fix parsing of gpio list The list of gpios is defined as optional but the code was failing to properly handle the case of no gpios, and also failing to check for errors reading the entry from the devicetree. This patch fixes the handling of optional gpios - this is a useful feature enabling the gpio-regulator to be used as a dummy variable voltage regulator without having to assign any real GPIO lines. Signed-off-by: Richard Fitzgerald Signed-off-by: Mark Brown --- drivers/regulator/gpio-regulator.c | 93 +++++++++++++++++++++----------------- 1 file changed, 51 insertions(+), 42 deletions(-) diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c index 86546c1c32c4..b42c7ec0017f 100644 --- a/drivers/regulator/gpio-regulator.c +++ b/drivers/regulator/gpio-regulator.c @@ -162,34 +162,41 @@ of_get_gpio_regulator_config(struct device *dev, struct device_node *np) config->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0); - /* Fetch GPIOs. */ - config->nr_gpios = of_gpio_count(np); - - config->gpios = devm_kzalloc(dev, - sizeof(struct gpio) * config->nr_gpios, - GFP_KERNEL); - if (!config->gpios) - return ERR_PTR(-ENOMEM); - - proplen = of_property_count_u32_elems(np, "gpios-states"); - /* optional property */ - if (proplen < 0) - proplen = 0; - - if (proplen > 0 && proplen != config->nr_gpios) { - dev_warn(dev, "gpios <-> gpios-states mismatch\n"); - proplen = 0; - } + /* Fetch GPIOs. - optional property*/ + ret = of_gpio_count(np); + if ((ret < 0) && (ret != -ENOENT)) + return ERR_PTR(ret); + + if (ret > 0) { + config->nr_gpios = ret; + config->gpios = devm_kzalloc(dev, + sizeof(struct gpio) * config->nr_gpios, + GFP_KERNEL); + if (!config->gpios) + return ERR_PTR(-ENOMEM); + + proplen = of_property_count_u32_elems(np, "gpios-states"); + /* optional property */ + if (proplen < 0) + proplen = 0; + + if (proplen > 0 && proplen != config->nr_gpios) { + dev_warn(dev, "gpios <-> gpios-states mismatch\n"); + proplen = 0; + } - for (i = 0; i < config->nr_gpios; i++) { - gpio = of_get_named_gpio(np, "gpios", i); - if (gpio < 0) - break; - config->gpios[i].gpio = gpio; - if (proplen > 0) { - of_property_read_u32_index(np, "gpios-states", i, &ret); - if (ret) - config->gpios[i].flags = GPIOF_OUT_INIT_HIGH; + for (i = 0; i < config->nr_gpios; i++) { + gpio = of_get_named_gpio(np, "gpios", i); + if (gpio < 0) + break; + config->gpios[i].gpio = gpio; + if (proplen > 0) { + of_property_read_u32_index(np, "gpios-states", + i, &ret); + if (ret) + config->gpios[i].flags = + GPIOF_OUT_INIT_HIGH; + } } } @@ -261,13 +268,23 @@ static int gpio_regulator_probe(struct platform_device *pdev) goto err; } - drvdata->gpios = kmemdup(config->gpios, - config->nr_gpios * sizeof(struct gpio), - GFP_KERNEL); - if (drvdata->gpios == NULL) { - dev_err(&pdev->dev, "Failed to allocate gpio data\n"); - ret = -ENOMEM; - goto err_name; + if (config->nr_gpios != 0) { + drvdata->gpios = kmemdup(config->gpios, + config->nr_gpios * sizeof(struct gpio), + GFP_KERNEL); + if (drvdata->gpios == NULL) { + dev_err(&pdev->dev, "Failed to allocate gpio data\n"); + ret = -ENOMEM; + goto err_name; + } + + drvdata->nr_gpios = config->nr_gpios; + ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios); + if (ret) { + dev_err(&pdev->dev, + "Could not obtain regulator setting GPIOs: %d\n", ret); + goto err_memstate; + } } drvdata->states = kmemdup(config->states, @@ -301,14 +318,6 @@ static int gpio_regulator_probe(struct platform_device *pdev) goto err_memgpio; } - drvdata->nr_gpios = config->nr_gpios; - ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios); - if (ret) { - dev_err(&pdev->dev, - "Could not obtain regulator setting GPIOs: %d\n", ret); - goto err_memstate; - } - /* build initial state from gpio init data. */ state = 0; for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) { -- cgit v1.2.3