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authorHauke Mehrtens <hauke@hauke-m.de>2012-11-20 22:24:30 +0000
committerJohn Crispin <blogic@openwrt.org>2012-11-21 21:55:52 +0100
commitcf0936b06d8e98a157630e99f647e2ff6d29d7ad (patch)
tree651457e034e073d236e9b0e64e0008e4ed2e0150 /drivers/bcma/driver_gpio.c
parent3e8bb507edfb44dfb8b0e06574826e34a8f6291d (diff)
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bcma: add GPIO driver
Register a GPIO driver to access the GPIOs provided by the chip. The GPIOs of the SoC should always start at 0 and the other GPIOs could start at a random position. There is just one SoC in a system and when they start at 0 the number is predictable. Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de> Patchwork: http://patchwork.linux-mips.org/patch/4587 Acked-by: Florian Fainelli <florian@openwrt.org>
Diffstat (limited to 'drivers/bcma/driver_gpio.c')
-rw-r--r--drivers/bcma/driver_gpio.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/bcma/driver_gpio.c b/drivers/bcma/driver_gpio.c
new file mode 100644
index 000000000000..9a6f585da2d9
--- /dev/null
+++ b/drivers/bcma/driver_gpio.c
@@ -0,0 +1,98 @@
+/*
+ * Broadcom specific AMBA
+ * GPIO driver
+ *
+ * Copyright 2011, Broadcom Corporation
+ * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/gpio.h>
+#include <linux/export.h>
+#include <linux/bcma/bcma.h>
+
+#include "bcma_private.h"
+
+static inline struct bcma_drv_cc *bcma_gpio_get_cc(struct gpio_chip *chip)
+{
+ return container_of(chip, struct bcma_drv_cc, gpio);
+}
+
+static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ return !!bcma_chipco_gpio_in(cc, 1 << gpio);
+}
+
+static void bcma_gpio_set_value(struct gpio_chip *chip, unsigned gpio,
+ int value)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
+}
+
+static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ bcma_chipco_gpio_outen(cc, 1 << gpio, 0);
+ return 0;
+}
+
+static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
+ int value)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio);
+ bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
+ return 0;
+}
+
+static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ bcma_chipco_gpio_control(cc, 1 << gpio, 0);
+ /* clear pulldown */
+ bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0);
+ /* Set pullup */
+ bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio);
+
+ return 0;
+}
+
+static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio)
+{
+ struct bcma_drv_cc *cc = bcma_gpio_get_cc(chip);
+
+ /* clear pullup */
+ bcma_chipco_gpio_pullup(cc, 1 << gpio, 0);
+}
+
+int bcma_gpio_init(struct bcma_drv_cc *cc)
+{
+ struct gpio_chip *chip = &cc->gpio;
+
+ chip->label = "bcma_gpio";
+ chip->owner = THIS_MODULE;
+ chip->request = bcma_gpio_request;
+ chip->free = bcma_gpio_free;
+ chip->get = bcma_gpio_get_value;
+ chip->set = bcma_gpio_set_value;
+ chip->direction_input = bcma_gpio_direction_input;
+ chip->direction_output = bcma_gpio_direction_output;
+ chip->ngpio = 16;
+ /* There is just one SoC in one device and its GPIO addresses should be
+ * deterministic to address them more easily. The other buses could get
+ * a random base number. */
+ if (cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC)
+ chip->base = 0;
+ else
+ chip->base = -1;
+
+ return gpiochip_add(chip);
+}