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authorLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 09:40:46 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 10:09:12 -0800
commit8e5096607280d4e103389bfe8f8b7decbf538ff6 (patch)
tree60352a466e96c7b36d41263d7590ee79e0aaff35 /drivers/gpio/gpio-mcp23s08.c
parent02d0a752460ea5dab34ce36c9ddc9c682e846a0d (diff)
parentde755c330512364d3396c7da0c20b1c20b3b08b2 (diff)
downloadlinux-rt-8e5096607280d4e103389bfe8f8b7decbf538ff6.tar.gz
Merge tag 'gpio-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO tree bulk changes from Linus Walleij: "A big set this merge window, as we have much going on in this subsystem. The changes to other subsystems (notably a slew of ARM machines as I am doing away with their custom APIs) have all been ACKed to the extent possible. Major changes this time: - Some core improvements and cleanups to the new GPIO descriptor API. This seems to be working now so we can start the exodus to this API, moving gradually away from the global GPIO numberspace. - Incremental improvements to the ACPI GPIO core, and move the few GPIO ACPI clients we have to the GPIO descriptor API right *now* before we go any further. We actually managed to contain this *before* we started to litter the kernel with yet another hackish global numberspace for the ACPI GPIOs, which is a big win. - The RFkill GPIO driver and all platforms using it have been migrated to use the GPIO descriptors rather than fixed number assignments. Tegra machine has been migrated as part of this. - New drivers for MOXA ART, Xtensa GPIO32 and SMSC SCH311x. Those should be really good examples of how I expect a nice GPIO driver to look these days. - Do away with custom GPIO implementations on a major part of the ARM machines: ks8695, lpc32xx, mv78xx0. Make a first step towards the same in the horribly convoluted Samsung S3C include forest. We expect to continue to clean this up as we move forward. - Flag GPIO lines used for IRQ on adnp, bcm-kona, em, intel-mid and lynxpoint. This makes the GPIOlib core aware that a certain GPIO line is used for IRQs and can then enforce some semantics such as disallowing a GPIO line marked as in use for IRQ to be switched to output mode. - Drop all use of irq_set_chip_and_handler_name(). The name provided in these cases were just unhelpful tags like "mux" or "demux". - Extend the MCP23s08 driver to handle interrupts. - Minor incremental improvements for rcar, lynxpoint, em 74x164 and msm drivers. - Some non-urgent bug fixes here and there, duplicate #includes and that usual kind of cleanups" Fix up broken Kconfig file manually to make this all compile. * tag 'gpio-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (71 commits) gpio: mcp23s08: fix casting caused build warning gpio: mcp23s08: depend on OF_GPIO gpio: mcp23s08: Add irq functionality for i2c chips ARM: S5P[v210|c100|64x0]: Fix build error gpio: pxa: clamp gpio get value to [0,1] ARM: s3c24xx: explicit dependency on <plat/gpio-cfg.h> ARM: S3C[24|64]xx: move includes back under <mach/> scope Documentation / ACPI: update to GPIO descriptor API gpio / ACPI: get rid of acpi_gpio.h gpio / ACPI: register to ACPI events automatically mmc: sdhci-acpi: convert to use GPIO descriptor API ARM: s3c24xx: fix build error gpio: f7188x: set can_sleep attribute gpio: samsung: Update documentation gpio: samsung: Remove hardware.h inclusion gpio: xtensa: depend on HAVE_XTENSA_GPIO32 gpio: clps711x: Enable driver compilation with COMPILE_TEST gpio: clps711x: Use of_match_ptr() net: rfkill: gpio: convert to descriptor-based GPIO interface leds: s3c24xx: Fix build failure ...
Diffstat (limited to 'drivers/gpio/gpio-mcp23s08.c')
-rw-r--r--drivers/gpio/gpio-mcp23s08.c252
1 files changed, 245 insertions, 7 deletions
diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c
index 2deb0c5e54a4..1ac288ea810d 100644
--- a/drivers/gpio/gpio-mcp23s08.c
+++ b/drivers/gpio/gpio-mcp23s08.c
@@ -1,5 +1,13 @@
/*
- * MCP23S08 SPI/GPIO gpio expander driver
+ * MCP23S08 SPI/I2C GPIO gpio expander driver
+ *
+ * The inputs and outputs of the mcp23s08, mcp23s17, mcp23008 and mcp23017 are
+ * supported.
+ * For the I2C versions of the chips (mcp23008 and mcp23017) generation of
+ * interrupts is also supported.
+ * The hardware of the SPI versions of the chips (mcp23s08 and mcp23s17) is
+ * also capable of generating interrupts, but the linux driver does not
+ * support that yet.
*/
#include <linux/kernel.h>
@@ -12,7 +20,8 @@
#include <linux/spi/mcp23s08.h>
#include <linux/slab.h>
#include <asm/byteorder.h>
-#include <linux/of.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
#include <linux/of_device.h>
/**
@@ -34,6 +43,7 @@
#define MCP_DEFVAL 0x03
#define MCP_INTCON 0x04
#define MCP_IOCON 0x05
+# define IOCON_MIRROR (1 << 6)
# define IOCON_SEQOP (1 << 5)
# define IOCON_HAEN (1 << 3)
# define IOCON_ODR (1 << 2)
@@ -57,8 +67,14 @@ struct mcp23s08 {
u8 addr;
u16 cache[11];
+ u16 irq_rise;
+ u16 irq_fall;
+ int irq;
+ bool irq_controller;
/* lock protects the cached values */
struct mutex lock;
+ struct mutex irq_lock;
+ struct irq_domain *irq_domain;
struct gpio_chip chip;
@@ -77,6 +93,11 @@ struct mcp23s08_driver_data {
struct mcp23s08 chip[];
};
+/* This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+static struct lock_class_key gpio_lock_class;
+
/*----------------------------------------------------------------------*/
#if IS_ENABLED(CONFIG_I2C)
@@ -316,6 +337,195 @@ mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
}
/*----------------------------------------------------------------------*/
+static irqreturn_t mcp23s08_irq(int irq, void *data)
+{
+ struct mcp23s08 *mcp = data;
+ int intcap, intf, i;
+ unsigned int child_irq;
+
+ mutex_lock(&mcp->lock);
+ intf = mcp->ops->read(mcp, MCP_INTF);
+ if (intf < 0) {
+ mutex_unlock(&mcp->lock);
+ return IRQ_HANDLED;
+ }
+
+ mcp->cache[MCP_INTF] = intf;
+
+ intcap = mcp->ops->read(mcp, MCP_INTCAP);
+ if (intcap < 0) {
+ mutex_unlock(&mcp->lock);
+ return IRQ_HANDLED;
+ }
+
+ mcp->cache[MCP_INTCAP] = intcap;
+ mutex_unlock(&mcp->lock);
+
+
+ for (i = 0; i < mcp->chip.ngpio; i++) {
+ if ((BIT(i) & mcp->cache[MCP_INTF]) &&
+ ((BIT(i) & intcap & mcp->irq_rise) ||
+ (mcp->irq_fall & ~intcap & BIT(i)))) {
+ child_irq = irq_find_mapping(mcp->irq_domain, i);
+ handle_nested_irq(child_irq);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int mcp23s08_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
+
+ return irq_find_mapping(mcp->irq_domain, offset);
+}
+
+static void mcp23s08_irq_mask(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+ unsigned int pos = data->hwirq;
+
+ mcp->cache[MCP_GPINTEN] &= ~BIT(pos);
+}
+
+static void mcp23s08_irq_unmask(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+ unsigned int pos = data->hwirq;
+
+ mcp->cache[MCP_GPINTEN] |= BIT(pos);
+}
+
+static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+ unsigned int pos = data->hwirq;
+ int status = 0;
+
+ if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
+ mcp->cache[MCP_INTCON] &= ~BIT(pos);
+ mcp->irq_rise |= BIT(pos);
+ mcp->irq_fall |= BIT(pos);
+ } else if (type & IRQ_TYPE_EDGE_RISING) {
+ mcp->cache[MCP_INTCON] &= ~BIT(pos);
+ mcp->irq_rise |= BIT(pos);
+ mcp->irq_fall &= ~BIT(pos);
+ } else if (type & IRQ_TYPE_EDGE_FALLING) {
+ mcp->cache[MCP_INTCON] &= ~BIT(pos);
+ mcp->irq_rise &= ~BIT(pos);
+ mcp->irq_fall |= BIT(pos);
+ } else
+ return -EINVAL;
+
+ return status;
+}
+
+static void mcp23s08_irq_bus_lock(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+
+ mutex_lock(&mcp->irq_lock);
+}
+
+static void mcp23s08_irq_bus_unlock(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+
+ mutex_lock(&mcp->lock);
+ mcp->ops->write(mcp, MCP_GPINTEN, mcp->cache[MCP_GPINTEN]);
+ mcp->ops->write(mcp, MCP_DEFVAL, mcp->cache[MCP_DEFVAL]);
+ mcp->ops->write(mcp, MCP_INTCON, mcp->cache[MCP_INTCON]);
+ mutex_unlock(&mcp->lock);
+ mutex_unlock(&mcp->irq_lock);
+}
+
+static unsigned int mcp23s08_irq_startup(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+
+ if (gpio_lock_as_irq(&mcp->chip, data->hwirq))
+ dev_err(mcp->chip.dev,
+ "unable to lock HW IRQ %lu for IRQ usage\n",
+ data->hwirq);
+
+ mcp23s08_irq_unmask(data);
+ return 0;
+}
+
+static void mcp23s08_irq_shutdown(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+
+ mcp23s08_irq_mask(data);
+ gpio_unlock_as_irq(&mcp->chip, data->hwirq);
+}
+
+static struct irq_chip mcp23s08_irq_chip = {
+ .name = "gpio-mcp23xxx",
+ .irq_mask = mcp23s08_irq_mask,
+ .irq_unmask = mcp23s08_irq_unmask,
+ .irq_set_type = mcp23s08_irq_set_type,
+ .irq_bus_lock = mcp23s08_irq_bus_lock,
+ .irq_bus_sync_unlock = mcp23s08_irq_bus_unlock,
+ .irq_startup = mcp23s08_irq_startup,
+ .irq_shutdown = mcp23s08_irq_shutdown,
+};
+
+static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
+{
+ struct gpio_chip *chip = &mcp->chip;
+ int err, irq, j;
+
+ mutex_init(&mcp->irq_lock);
+
+ mcp->irq_domain = irq_domain_add_linear(chip->of_node, chip->ngpio,
+ &irq_domain_simple_ops, mcp);
+ if (!mcp->irq_domain)
+ return -ENODEV;
+
+ err = devm_request_threaded_irq(chip->dev, mcp->irq, NULL, mcp23s08_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ dev_name(chip->dev), mcp);
+ if (err != 0) {
+ dev_err(chip->dev, "unable to request IRQ#%d: %d\n",
+ mcp->irq, err);
+ return err;
+ }
+
+ chip->to_irq = mcp23s08_gpio_to_irq;
+
+ for (j = 0; j < mcp->chip.ngpio; j++) {
+ irq = irq_create_mapping(mcp->irq_domain, j);
+ irq_set_lockdep_class(irq, &gpio_lock_class);
+ irq_set_chip_data(irq, mcp);
+ irq_set_chip(irq, &mcp23s08_irq_chip);
+ irq_set_nested_thread(irq, true);
+#ifdef CONFIG_ARM
+ set_irq_flags(irq, IRQF_VALID);
+#else
+ irq_set_noprobe(irq);
+#endif
+ }
+ return 0;
+}
+
+static void mcp23s08_irq_teardown(struct mcp23s08 *mcp)
+{
+ unsigned int irq, i;
+
+ free_irq(mcp->irq, mcp);
+
+ for (i = 0; i < mcp->chip.ngpio; i++) {
+ irq = irq_find_mapping(mcp->irq_domain, i);
+ if (irq > 0)
+ irq_dispose_mapping(irq);
+ }
+
+ irq_domain_remove(mcp->irq_domain);
+}
+
+/*----------------------------------------------------------------------*/
#ifdef CONFIG_DEBUG_FS
@@ -370,10 +580,11 @@ done:
/*----------------------------------------------------------------------*/
static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
- void *data, unsigned addr,
- unsigned type, unsigned base, unsigned pullups)
+ void *data, unsigned addr, unsigned type,
+ unsigned base, unsigned pullups)
{
int status;
+ bool mirror = false;
mutex_init(&mcp->lock);
@@ -425,20 +636,32 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
}
mcp->chip.base = base;
- mcp->chip.can_sleep = 1;
+ mcp->chip.can_sleep = true;
mcp->chip.dev = dev;
mcp->chip.owner = THIS_MODULE;
/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
* and MCP_IOCON.HAEN = 1, so we work with all chips.
*/
+
status = mcp->ops->read(mcp, MCP_IOCON);
if (status < 0)
goto fail;
- if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) {
+
+ mcp->irq_controller = of_property_read_bool(mcp->chip.of_node,
+ "interrupt-controller");
+ if (mcp->irq && mcp->irq_controller && (type == MCP_TYPE_017))
+ mirror = of_property_read_bool(mcp->chip.of_node,
+ "microchip,irq-mirror");
+
+ if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror) {
/* mcp23s17 has IOCON twice, make sure they are in sync */
status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
status |= IOCON_HAEN | (IOCON_HAEN << 8);
+ status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
+ if (mirror)
+ status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
+
status = mcp->ops->write(mcp, MCP_IOCON, status);
if (status < 0)
goto fail;
@@ -470,6 +693,16 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
}
status = gpiochip_add(&mcp->chip);
+ if (status < 0)
+ goto fail;
+
+ if (mcp->irq && mcp->irq_controller) {
+ status = mcp23s08_irq_setup(mcp);
+ if (status) {
+ mcp23s08_irq_teardown(mcp);
+ goto fail;
+ }
+ }
fail:
if (status < 0)
dev_dbg(dev, "can't setup chip %d, --> %d\n",
@@ -546,6 +779,7 @@ static int mcp230xx_probe(struct i2c_client *client,
if (match || !pdata) {
base = -1;
pullups = 0;
+ client->irq = irq_of_parse_and_map(client->dev.of_node, 0);
} else {
if (!gpio_is_valid(pdata->base)) {
dev_dbg(&client->dev, "invalid platform data\n");
@@ -559,6 +793,7 @@ static int mcp230xx_probe(struct i2c_client *client,
if (!mcp)
return -ENOMEM;
+ mcp->irq = client->irq;
status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
id->driver_data, base, pullups);
if (status)
@@ -579,6 +814,9 @@ static int mcp230xx_remove(struct i2c_client *client)
struct mcp23s08 *mcp = i2c_get_clientdata(client);
int status;
+ if (client->irq && mcp->irq_controller)
+ mcp23s08_irq_teardown(mcp);
+
status = gpiochip_remove(&mcp->chip);
if (status == 0)
kfree(mcp);
@@ -640,7 +878,7 @@ static int mcp23s08_probe(struct spi_device *spi)
match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
if (match) {
- type = (int)match->data;
+ type = (int)(uintptr_t)match->data;
status = of_property_read_u32(spi->dev.of_node,
"microchip,spi-present-mask", &spi_present_mask);
if (status) {