Merge branch 'gpio-reserved-ranges' into devel

5 files changed, 167 insertions, 11 deletions

diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index b5de08e3b1a2..a7c31de29362 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -151,9 +151,9 @@ in a lot of designs, some using all 32 bits, some using 18 and some using
 first 18 GPIOs, at local offset 0 .. 17, are in use.
 
 If these GPIOs do not happen to be the first N GPIOs at offset 0...N-1, an
-additional bitmask is needed to specify which GPIOs are actually in use,
-and which are dummies. The bindings for this case has not yet been
-specified, but should be specified if/when such hardware appears.
+additional set of tuples is needed to specify which GPIOs are unusable, with
+the gpio-reserved-ranges binding. This property indicates the start and size
+of the GPIOs that can't be used.
 
 Optionally, a GPIO controller may have a "gpio-line-names" property. This is
 an array of strings defining the names of the GPIO lines going out of the
@@ -178,6 +178,7 @@ gpio-controller@00000000 {
         gpio-controller;
         #gpio-cells = <2>;
         ngpios = <18>;
+        gpio-reserved-ranges = <0 4>, <12 2>;
         gpio-line-names = "MMC-CD", "MMC-WP", "VDD eth", "RST eth", "LED R",
                 "LED G", "LED B", "Col A", "Col B", "Col C", "Col D",
                 "Row A", "Row B", "Row C", "Row D", "NMI button",
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 84e5a9df2344..ed81d9a6316f 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -511,6 +511,28 @@ void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
 }
 EXPORT_SYMBOL(of_mm_gpiochip_remove);
 
+static void of_gpiochip_init_valid_mask(struct gpio_chip *chip)
+{
+        int len, i;
+        u32 start, count;
+        struct device_node *np = chip->of_node;
+
+        len = of_property_count_u32_elems(np,  "gpio-reserved-ranges");
+        if (len < 0 || len % 2 != 0)
+                return;
+
+        for (i = 0; i < len; i += 2) {
+                of_property_read_u32_index(np, "gpio-reserved-ranges",
+                                           i, &start);
+                of_property_read_u32_index(np, "gpio-reserved-ranges",
+                                           i + 1, &count);
+                if (start >= chip->ngpio || start + count >= chip->ngpio)
+                        continue;
+
+                bitmap_clear(chip->valid_mask, start, count);
+        }
+};
+
 #ifdef CONFIG_PINCTRL
 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
 {
@@ -615,6 +637,8 @@ int of_gpiochip_add(struct gpio_chip *chip)
         if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
                 return -EINVAL;
 
+        of_gpiochip_init_valid_mask(chip);
+
         status = of_gpiochip_add_pin_range(chip);
         if (status)
                 return status;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f220d844b607..43aeb07343ec 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -337,6 +337,57 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
         return 0;
 }
 
+static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
+{
+        unsigned long *p;
+
+        p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL);
+        if (!p)
+                return NULL;
+
+        /* Assume by default all GPIOs are valid */
+        bitmap_fill(p, chip->ngpio);
+
+        return p;
+}
+
+static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip)
+{
+#ifdef CONFIG_OF_GPIO
+        int size;
+        struct device_node *np = gpiochip->of_node;
+
+        size = of_property_count_u32_elems(np,  "gpio-reserved-ranges");
+        if (size > 0 && size % 2 == 0)
+                gpiochip->need_valid_mask = true;
+#endif
+
+        if (!gpiochip->need_valid_mask)
+                return 0;
+
+        gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip);
+        if (!gpiochip->valid_mask)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
+{
+        kfree(gpiochip->valid_mask);
+        gpiochip->valid_mask = NULL;
+}
+
+bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
+                                unsigned int offset)
+{
+        /* No mask means all valid */
+        if (likely(!gpiochip->valid_mask))
+                return true;
+        return test_bit(offset, gpiochip->valid_mask);
+}
+EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
+
 /*
  * GPIO line handle management
  */
@@ -1261,6 +1312,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
         if (status)
                 goto err_remove_from_list;
 
+        status = gpiochip_init_valid_mask(chip);
+        if (status)
+                goto err_remove_irqchip_mask;
+
         status = gpiochip_add_irqchip(chip, lock_key, request_key);
         if (status)
                 goto err_remove_chip;
@@ -1290,6 +1345,8 @@ err_remove_chip:
         acpi_gpiochip_remove(chip);
         gpiochip_free_hogs(chip);
         of_gpiochip_remove(chip);
+        gpiochip_free_valid_mask(chip);
+err_remove_irqchip_mask:
         gpiochip_irqchip_free_valid_mask(chip);
 err_remove_from_list:
         spin_lock_irqsave(&gpio_lock, flags);
@@ -1346,6 +1403,7 @@ void gpiochip_remove(struct gpio_chip *chip)
         acpi_gpiochip_remove(chip);
         gpiochip_remove_pin_ranges(chip);
         of_gpiochip_remove(chip);
+        gpiochip_free_valid_mask(chip);
         /*
          * We accept no more calls into the driver from this point, so
          * NULL the driver data pointer
@@ -1506,14 +1564,10 @@ static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
         if (!gpiochip->irq.need_valid_mask)
                 return 0;
 
-        gpiochip->irq.valid_mask = kcalloc(BITS_TO_LONGS(gpiochip->ngpio),
-                                           sizeof(long), GFP_KERNEL);
+        gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip);
         if (!gpiochip->irq.valid_mask)
                 return -ENOMEM;
 
-        /* Assume by default all GPIOs are valid */
-        bitmap_fill(gpiochip->irq.valid_mask, gpiochip->ngpio);
-
         return 0;
 }
 
@@ -1526,6 +1580,8 @@ static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
                                 unsigned int offset)
 {
+        if (!gpiochip_line_is_valid(gpiochip, offset))
+                return false;
         /* No mask means all valid */
         if (likely(!gpiochip->irq.valid_mask))
                 return true;
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index 495432f3341b..e7abc8ba222b 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -105,6 +105,14 @@ static const struct pinctrl_ops msm_pinctrl_ops = {
         .dt_free_map            = pinctrl_utils_free_map,
 };
 
+static int msm_pinmux_request(struct pinctrl_dev *pctldev, unsigned offset)
+{
+        struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
+        struct gpio_chip *chip = &pctrl->chip;
+
+        return gpiochip_line_is_valid(chip, offset) ? 0 : -EINVAL;
+}
+
 static int msm_get_functions_count(struct pinctrl_dev *pctldev)
 {
         struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
@@ -166,6 +174,7 @@ static int msm_pinmux_set_mux(struct pinctrl_dev *pctldev,
 }
 
 static const struct pinmux_ops msm_pinmux_ops = {
+        .request                = msm_pinmux_request,
         .get_functions_count    = msm_get_functions_count,
         .get_function_name      = msm_get_function_name,
         .get_function_groups    = msm_get_function_groups,
@@ -506,6 +515,9 @@ static void msm_gpio_dbg_show_one(struct seq_file *s,
                 "pull up"
         };
 
+        if (!gpiochip_line_is_valid(chip, offset))
+                return;
+
         g = &pctrl->soc->groups[offset];
         ctl_reg = readl(pctrl->regs + g->ctl_reg);
 
@@ -517,6 +529,7 @@ static void msm_gpio_dbg_show_one(struct seq_file *s,
         seq_printf(s, " %-8s: %-3s %d", g->name, is_out ? "out" : "in", func);
         seq_printf(s, " %dmA", msm_regval_to_drive(drive));
         seq_printf(s, " %s", pulls[pull]);
+        seq_puts(s, "\n");
 }
 
 static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
@@ -524,10 +537,8 @@ static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
         unsigned gpio = chip->base;
         unsigned i;
 
-        for (i = 0; i < chip->ngpio; i++, gpio++) {
+        for (i = 0; i < chip->ngpio; i++, gpio++)
                 msm_gpio_dbg_show_one(s, NULL, chip, i, gpio);
-                seq_puts(s, "\n");
-        }
 }
 
 #else
@@ -808,6 +819,46 @@ static void msm_gpio_irq_handler(struct irq_desc *desc)
         chained_irq_exit(chip, desc);
 }
 
+static int msm_gpio_init_valid_mask(struct gpio_chip *chip,
+                                    struct msm_pinctrl *pctrl)
+{
+        int ret;
+        unsigned int len, i;
+        unsigned int max_gpios = pctrl->soc->ngpios;
+        u16 *tmp;
+
+        /* The number of GPIOs in the ACPI tables */
+        len = ret = device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0);
+        if (ret < 0)
+                return 0;
+
+        if (ret > max_gpios)
+                return -EINVAL;
+
+        tmp = kmalloc_array(len, sizeof(*tmp), GFP_KERNEL);
+        if (!tmp)
+                return -ENOMEM;
+
+        ret = device_property_read_u16_array(pctrl->dev, "gpios", tmp, len);
+        if (ret < 0) {
+                dev_err(pctrl->dev, "could not read list of GPIOs\n");
+                goto out;
+        }
+
+        bitmap_zero(chip->valid_mask, max_gpios);
+        for (i = 0; i < len; i++)
+                set_bit(tmp[i], chip->valid_mask);
+
+out:
+        kfree(tmp);
+        return ret;
+}
+
+static bool msm_gpio_needs_valid_mask(struct msm_pinctrl *pctrl)
+{
+        return device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0) > 0;
+}
+
 static int msm_gpio_init(struct msm_pinctrl *pctrl)
 {
         struct gpio_chip *chip;
@@ -824,6 +875,7 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
         chip->parent = pctrl->dev;
         chip->owner = THIS_MODULE;
         chip->of_node = pctrl->dev->of_node;
+        chip->need_valid_mask = msm_gpio_needs_valid_mask(pctrl);
 
         ret = gpiochip_add_data(&pctrl->chip, pctrl);
         if (ret) {
@@ -831,6 +883,13 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
                 return ret;
         }
 
+        ret = msm_gpio_init_valid_mask(chip, pctrl);
+        if (ret) {
+                dev_err(pctrl->dev, "Failed to setup irq valid bits\n");
+                gpiochip_remove(&pctrl->chip);
+                return ret;
+        }
+
         ret = gpiochip_add_pin_range(&pctrl->chip, dev_name(pctrl->dev), 0, 0, chip->ngpio);
         if (ret) {
                 dev_err(pctrl->dev, "Failed to add pin range\n");
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 1ba9a331ec51..5382b5183b7e 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -288,6 +288,21 @@ struct gpio_chip {
         struct gpio_irq_chip irq;
 #endif
 
+        /**
+         * @need_valid_mask:
+         *
+         * If set core allocates @valid_mask with all bits set to one.
+         */
+        bool need_valid_mask;
+
+        /**
+         * @valid_mask:
+         *
+         * If not %NULL holds bitmask of GPIOs which are valid to be used
+         * from the chip.
+         */
+        unsigned long *valid_mask;
+
 #if defined(CONFIG_OF_GPIO)
         /*
          * If CONFIG_OF is enabled, then all GPIO controllers described in the
@@ -384,6 +399,7 @@ bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset);
 
 /* Sleep persistence inquiry for drivers */
 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset);
+bool gpiochip_line_is_valid(const struct gpio_chip *chip, unsigned int offset);
 
 /* get driver data */
 void *gpiochip_get_data(struct gpio_chip *chip);