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authorLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 11:31:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-06-08 11:31:16 -0700
commit3f17ea6dea8ba5668873afa54628a91aaa3fb1c0 (patch)
treeafbeb2accd4c2199ddd705ae943995b143a0af02 /drivers/tty/serial/serial_mctrl_gpio.c
parent1860e379875dfe7271c649058aeddffe5afd9d0d (diff)
parent1a5700bc2d10cd379a795fd2bb377a190af5acd4 (diff)
Merge branch 'next' (accumulated 3.16 merge window patches) into master
Now that 3.15 is released, this merges the 'next' branch into 'master', bringing us to the normal situation where my 'master' branch is the merge window. * accumulated work in next: (6809 commits) ufs: sb mutex merge + mutex_destroy powerpc: update comments for generic idle conversion cris: update comments for generic idle conversion idle: remove cpu_idle() forward declarations nbd: zero from and len fields in NBD_CMD_DISCONNECT. mm: convert some level-less printks to pr_* MAINTAINERS: adi-buildroot-devel is moderated MAINTAINERS: add linux-api for review of API/ABI changes mm/kmemleak-test.c: use pr_fmt for logging fs/dlm/debug_fs.c: replace seq_printf by seq_puts fs/dlm/lockspace.c: convert simple_str to kstr fs/dlm/config.c: convert simple_str to kstr mm: mark remap_file_pages() syscall as deprecated mm: memcontrol: remove unnecessary memcg argument from soft limit functions mm: memcontrol: clean up memcg zoneinfo lookup mm/memblock.c: call kmemleak directly from memblock_(alloc|free) mm/mempool.c: update the kmemleak stack trace for mempool allocations lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations mm: introduce kmemleak_update_trace() mm/kmemleak.c: use %u to print ->checksum ...
Diffstat (limited to 'drivers/tty/serial/serial_mctrl_gpio.c')
-rw-r--r--drivers/tty/serial/serial_mctrl_gpio.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_mctrl_gpio.c b/drivers/tty/serial/serial_mctrl_gpio.c
new file mode 100644
index 00000000000..bf9560ffe3f
--- /dev/null
+++ b/drivers/tty/serial/serial_mctrl_gpio.c
@@ -0,0 +1,143 @@
+/*
+ * Helpers for controlling modem lines via GPIO
+ *
+ * Copyright (C) 2014 Paratronic S.A.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <uapi/asm-generic/termios.h>
+
+#include "serial_mctrl_gpio.h"
+
+struct mctrl_gpios {
+ struct gpio_desc *gpio[UART_GPIO_MAX];
+};
+
+static const struct {
+ const char *name;
+ unsigned int mctrl;
+ bool dir_out;
+} mctrl_gpios_desc[UART_GPIO_MAX] = {
+ { "cts", TIOCM_CTS, false, },
+ { "dsr", TIOCM_DSR, false, },
+ { "dcd", TIOCM_CD, false, },
+ { "rng", TIOCM_RNG, false, },
+ { "rts", TIOCM_RTS, true, },
+ { "dtr", TIOCM_DTR, true, },
+ { "out1", TIOCM_OUT1, true, },
+ { "out2", TIOCM_OUT2, true, },
+};
+
+void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
+{
+ enum mctrl_gpio_idx i;
+
+ if (IS_ERR_OR_NULL(gpios))
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; i++)
+ if (!IS_ERR_OR_NULL(gpios->gpio[i]) &&
+ mctrl_gpios_desc[i].dir_out)
+ gpiod_set_value(gpios->gpio[i],
+ !!(mctrl & mctrl_gpios_desc[i].mctrl));
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_set);
+
+struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
+ enum mctrl_gpio_idx gidx)
+{
+ if (!IS_ERR_OR_NULL(gpios) && !IS_ERR_OR_NULL(gpios->gpio[gidx]))
+ return gpios->gpio[gidx];
+ else
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);
+
+unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
+{
+ enum mctrl_gpio_idx i;
+
+ /*
+ * return it unchanged if the structure is not allocated
+ */
+ if (IS_ERR_OR_NULL(gpios))
+ return *mctrl;
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ if (!IS_ERR_OR_NULL(gpios->gpio[i]) &&
+ !mctrl_gpios_desc[i].dir_out) {
+ if (gpiod_get_value(gpios->gpio[i]))
+ *mctrl |= mctrl_gpios_desc[i].mctrl;
+ else
+ *mctrl &= ~mctrl_gpios_desc[i].mctrl;
+ }
+ }
+
+ return *mctrl;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_get);
+
+struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx)
+{
+ struct mctrl_gpios *gpios;
+ enum mctrl_gpio_idx i;
+ int err;
+
+ gpios = devm_kzalloc(dev, sizeof(*gpios), GFP_KERNEL);
+ if (!gpios)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ gpios->gpio[i] = devm_gpiod_get_index(dev,
+ mctrl_gpios_desc[i].name,
+ idx);
+
+ /*
+ * The GPIOs are maybe not all filled,
+ * this is not an error.
+ */
+ if (IS_ERR_OR_NULL(gpios->gpio[i]))
+ continue;
+
+ if (mctrl_gpios_desc[i].dir_out)
+ err = gpiod_direction_output(gpios->gpio[i], 0);
+ else
+ err = gpiod_direction_input(gpios->gpio[i]);
+ if (err) {
+ dev_dbg(dev, "Unable to set direction for %s GPIO",
+ mctrl_gpios_desc[i].name);
+ devm_gpiod_put(dev, gpios->gpio[i]);
+ gpios->gpio[i] = NULL;
+ }
+ }
+
+ return gpios;
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_init);
+
+void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
+{
+ enum mctrl_gpio_idx i;
+
+ if (IS_ERR_OR_NULL(gpios))
+ return;
+
+ for (i = 0; i < UART_GPIO_MAX; i++)
+ if (!IS_ERR_OR_NULL(gpios->gpio[i]))
+ devm_gpiod_put(dev, gpios->gpio[i]);
+ devm_kfree(dev, gpios);
+}
+EXPORT_SYMBOL_GPL(mctrl_gpio_free);