gpio: add interrupt handling capability to max732x
Most of the GPIO expanders supported by the max732x driver have interrupt generation capability by reporting changes on input pins through an INT# pin. This patch implements the irq_chip functionnality (edge detection only). Signed-off-by: Marc Zyngier <maz@misterjones.org> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Jebediah Huang <jebediah.huang@gmail.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Marc Zyngier
Linus Torvalds
parent
0af62f4d1e
commit
a80a0bbee4
3 changed files with 346 additions and 19 deletions
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@ -139,6 +139,13 @@ config GPIO_MAX732X
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Board setup code must specify the model to use, and the start
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number for these GPIOs.
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config GPIO_MAX732X_IRQ
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bool "Interrupt controller support for MAX732x"
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depends on GPIO_MAX732X=y && GENERIC_HARDIRQS
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help
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Say yes here to enable the max732x to be used as an interrupt
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controller. It requires the driver to be built in the kernel.
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config GPIO_PCA953X
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tristate "PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports"
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depends on I2C
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@ -17,7 +17,8 @@
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/gpio.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/i2c.h>
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#include <linux/i2c/max732x.h>
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@ -31,7 +32,8 @@
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* - Open Drain I/O
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*
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* designated by 'O', 'I' and 'P' individually according to MAXIM's
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* datasheets.
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* datasheets. 'I' and 'P' ports are interrupt capables, some with
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* a dedicated interrupt mask.
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*
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* There are two groups of I/O ports, each group usually includes
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* up to 8 I/O ports, and is accessed by a specific I2C address:
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@ -44,7 +46,8 @@
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*
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* Within each group of ports, there are five known combinations of
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* I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for
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* the detailed organization of these ports.
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* the detailed organization of these ports. Only Goup A is interrupt
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* capable.
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*
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* GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16',
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* and GPIOs from GROUP_A are numbered before those from GROUP_B
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@ -68,16 +71,47 @@
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#define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */
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#define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */
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#define INT_NONE 0x0 /* No interrupt capability */
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#define INT_NO_MASK 0x1 /* Has interrupts, no mask */
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#define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */
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#define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */
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#define INT_CAPS(x) (((uint64_t)(x)) << 32)
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enum {
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MAX7319,
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MAX7320,
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MAX7321,
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MAX7322,
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MAX7323,
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MAX7324,
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MAX7325,
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MAX7326,
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MAX7327,
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};
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static uint64_t max732x_features[] = {
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[MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK),
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[MAX7320] = GROUP_B(IO_8O),
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[MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK),
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[MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK),
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[MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK),
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[MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
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[MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
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[MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK),
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[MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK),
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};
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static const struct i2c_device_id max732x_id[] = {
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{ "max7319", GROUP_A(IO_8I) },
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{ "max7320", GROUP_B(IO_8O) },
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{ "max7321", GROUP_A(IO_8P) },
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{ "max7322", GROUP_A(IO_4I4O) },
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{ "max7323", GROUP_A(IO_4P4O) },
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{ "max7324", GROUP_A(IO_8I) | GROUP_B(IO_8O) },
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{ "max7325", GROUP_A(IO_8P) | GROUP_B(IO_8O) },
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{ "max7326", GROUP_A(IO_4I4O) | GROUP_B(IO_8O) },
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{ "max7327", GROUP_A(IO_4P4O) | GROUP_B(IO_8O) },
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{ "max7319", MAX7319 },
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{ "max7320", MAX7320 },
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{ "max7321", MAX7321 },
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{ "max7322", MAX7322 },
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{ "max7323", MAX7323 },
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{ "max7324", MAX7324 },
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{ "max7325", MAX7325 },
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{ "max7326", MAX7326 },
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{ "max7327", MAX7327 },
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{ },
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};
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MODULE_DEVICE_TABLE(i2c, max732x_id);
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@ -96,9 +130,19 @@ struct max732x_chip {
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struct mutex lock;
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uint8_t reg_out[2];
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#ifdef CONFIG_GPIO_MAX732X_IRQ
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struct mutex irq_lock;
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int irq_base;
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uint8_t irq_mask;
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uint8_t irq_mask_cur;
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uint8_t irq_trig_raise;
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uint8_t irq_trig_fall;
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uint8_t irq_features;
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#endif
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};
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static int max732x_write(struct max732x_chip *chip, int group_a, uint8_t val)
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static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val)
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{
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struct i2c_client *client;
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int ret;
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@ -113,7 +157,7 @@ static int max732x_write(struct max732x_chip *chip, int group_a, uint8_t val)
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return 0;
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}
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static int max732x_read(struct max732x_chip *chip, int group_a, uint8_t *val)
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static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val)
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{
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struct i2c_client *client;
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int ret;
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@ -142,7 +186,7 @@ static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off)
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chip = container_of(gc, struct max732x_chip, gpio_chip);
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ret = max732x_read(chip, is_group_a(chip, off), ®_val);
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ret = max732x_readb(chip, is_group_a(chip, off), ®_val);
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if (ret < 0)
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return 0;
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@ -162,7 +206,7 @@ static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
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reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0];
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reg_out = (val) ? reg_out | mask : reg_out & ~mask;
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ret = max732x_write(chip, is_group_a(chip, off), reg_out);
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ret = max732x_writeb(chip, is_group_a(chip, off), reg_out);
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if (ret < 0)
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goto out;
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@ -209,12 +253,278 @@ static int max732x_gpio_direction_output(struct gpio_chip *gc,
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return 0;
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}
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#ifdef CONFIG_GPIO_MAX732X_IRQ
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static int max732x_writew(struct max732x_chip *chip, uint16_t val)
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{
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int ret;
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val = cpu_to_le16(val);
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ret = i2c_master_send(chip->client_group_a, (char *)&val, 2);
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if (ret < 0) {
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dev_err(&chip->client_group_a->dev, "failed writing\n");
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return ret;
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}
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return 0;
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}
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static int max732x_readw(struct max732x_chip *chip, uint16_t *val)
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{
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int ret;
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ret = i2c_master_recv(chip->client_group_a, (char *)val, 2);
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if (ret < 0) {
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dev_err(&chip->client_group_a->dev, "failed reading\n");
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return ret;
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}
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*val = le16_to_cpu(*val);
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return 0;
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}
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static void max732x_irq_update_mask(struct max732x_chip *chip)
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{
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uint16_t msg;
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if (chip->irq_mask == chip->irq_mask_cur)
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return;
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chip->irq_mask = chip->irq_mask_cur;
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if (chip->irq_features == INT_NO_MASK)
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return;
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mutex_lock(&chip->lock);
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switch (chip->irq_features) {
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case INT_INDEP_MASK:
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msg = (chip->irq_mask << 8) | chip->reg_out[0];
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max732x_writew(chip, msg);
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break;
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case INT_MERGED_MASK:
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msg = chip->irq_mask | chip->reg_out[0];
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max732x_writeb(chip, 1, (uint8_t)msg);
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break;
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}
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mutex_unlock(&chip->lock);
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}
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static int max732x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
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{
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struct max732x_chip *chip;
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chip = container_of(gc, struct max732x_chip, gpio_chip);
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return chip->irq_base + off;
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}
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static void max732x_irq_mask(unsigned int irq)
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{
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struct max732x_chip *chip = get_irq_chip_data(irq);
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chip->irq_mask_cur &= ~(1 << (irq - chip->irq_base));
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}
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static void max732x_irq_unmask(unsigned int irq)
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{
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struct max732x_chip *chip = get_irq_chip_data(irq);
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chip->irq_mask_cur |= 1 << (irq - chip->irq_base);
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}
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static void max732x_irq_bus_lock(unsigned int irq)
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{
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struct max732x_chip *chip = get_irq_chip_data(irq);
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mutex_lock(&chip->irq_lock);
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chip->irq_mask_cur = chip->irq_mask;
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}
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static void max732x_irq_bus_sync_unlock(unsigned int irq)
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{
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struct max732x_chip *chip = get_irq_chip_data(irq);
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max732x_irq_update_mask(chip);
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mutex_unlock(&chip->irq_lock);
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}
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static int max732x_irq_set_type(unsigned int irq, unsigned int type)
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{
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struct max732x_chip *chip = get_irq_chip_data(irq);
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uint16_t off = irq - chip->irq_base;
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uint16_t mask = 1 << off;
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if (!(mask & chip->dir_input)) {
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dev_dbg(&chip->client->dev, "%s port %d is output only\n",
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chip->client->name, off);
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return -EACCES;
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}
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if (!(type & IRQ_TYPE_EDGE_BOTH)) {
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dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
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irq, type);
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return -EINVAL;
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}
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if (type & IRQ_TYPE_EDGE_FALLING)
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chip->irq_trig_fall |= mask;
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else
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chip->irq_trig_fall &= ~mask;
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if (type & IRQ_TYPE_EDGE_RISING)
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chip->irq_trig_raise |= mask;
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else
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chip->irq_trig_raise &= ~mask;
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return max732x_gpio_direction_input(&chip->gpio_chip, off);
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}
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static struct irq_chip max732x_irq_chip = {
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.name = "max732x",
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.mask = max732x_irq_mask,
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.unmask = max732x_irq_unmask,
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.bus_lock = max732x_irq_bus_lock,
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.bus_sync_unlock = max732x_irq_bus_sync_unlock,
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.set_type = max732x_irq_set_type,
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};
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static uint8_t max732x_irq_pending(struct max732x_chip *chip)
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{
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uint8_t cur_stat;
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uint8_t old_stat;
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uint8_t trigger;
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uint8_t pending;
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uint16_t status;
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int ret;
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ret = max732x_readw(chip, &status);
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if (ret)
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return 0;
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trigger = status >> 8;
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trigger &= chip->irq_mask;
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if (!trigger)
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return 0;
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cur_stat = status & 0xFF;
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cur_stat &= chip->irq_mask;
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old_stat = cur_stat ^ trigger;
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pending = (old_stat & chip->irq_trig_fall) |
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(cur_stat & chip->irq_trig_raise);
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pending &= trigger;
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return pending;
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}
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static irqreturn_t max732x_irq_handler(int irq, void *devid)
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{
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struct max732x_chip *chip = devid;
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uint8_t pending;
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uint8_t level;
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pending = max732x_irq_pending(chip);
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if (!pending)
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return IRQ_HANDLED;
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do {
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level = __ffs(pending);
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handle_nested_irq(level + chip->irq_base);
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pending &= ~(1 << level);
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} while (pending);
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return IRQ_HANDLED;
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}
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static int max732x_irq_setup(struct max732x_chip *chip,
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const struct i2c_device_id *id)
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{
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struct i2c_client *client = chip->client;
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struct max732x_platform_data *pdata = client->dev.platform_data;
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int has_irq = max732x_features[id->driver_data] >> 32;
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int ret;
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if (pdata->irq_base && has_irq != INT_NONE) {
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int lvl;
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chip->irq_base = pdata->irq_base;
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chip->irq_features = has_irq;
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mutex_init(&chip->irq_lock);
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for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
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int irq = lvl + chip->irq_base;
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if (!(chip->dir_input & (1 << lvl)))
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continue;
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set_irq_chip_data(irq, chip);
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set_irq_chip_and_handler(irq, &max732x_irq_chip,
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handle_edge_irq);
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set_irq_nested_thread(irq, 1);
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#ifdef CONFIG_ARM
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set_irq_flags(irq, IRQF_VALID);
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#else
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set_irq_noprobe(irq);
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#endif
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}
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ret = request_threaded_irq(client->irq,
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NULL,
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max732x_irq_handler,
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IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
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dev_name(&client->dev), chip);
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if (ret) {
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dev_err(&client->dev, "failed to request irq %d\n",
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client->irq);
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goto out_failed;
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}
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chip->gpio_chip.to_irq = max732x_gpio_to_irq;
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}
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return 0;
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out_failed:
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chip->irq_base = 0;
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return ret;
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}
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static void max732x_irq_teardown(struct max732x_chip *chip)
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{
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if (chip->irq_base)
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free_irq(chip->client->irq, chip);
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}
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#else /* CONFIG_GPIO_MAX732X_IRQ */
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static int max732x_irq_setup(struct max732x_chip *chip,
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const struct i2c_device_id *id)
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{
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struct i2c_client *client = chip->client;
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struct max732x_platform_data *pdata = client->dev.platform_data;
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int has_irq = max732x_features[id->driver_data] >> 32;
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if (pdata->irq_base && has_irq != INT_NONE)
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dev_warn(&client->dev, "interrupt support not compiled in\n");
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return 0;
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}
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static void max732x_irq_teardown(struct max732x_chip *chip)
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{
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}
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#endif
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static int __devinit max732x_setup_gpio(struct max732x_chip *chip,
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const struct i2c_device_id *id,
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unsigned gpio_start)
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{
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struct gpio_chip *gc = &chip->gpio_chip;
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uint32_t id_data = id->driver_data;
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uint32_t id_data = (uint32_t)max732x_features[id->driver_data];
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int i, port = 0;
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for (i = 0; i < 16; i++, id_data >>= 2) {
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@ -306,9 +616,13 @@ static int __devinit max732x_probe(struct i2c_client *client,
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mutex_init(&chip->lock);
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max732x_read(chip, is_group_a(chip, 0), &chip->reg_out[0]);
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max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]);
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if (nr_port > 7)
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max732x_read(chip, is_group_a(chip, 8), &chip->reg_out[1]);
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max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]);
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||||
ret = max732x_irq_setup(chip, id);
|
||||
if (ret)
|
||||
goto out_failed;
|
||||
|
||||
ret = gpiochip_add(&chip->gpio_chip);
|
||||
if (ret)
|
||||
|
|
@ -325,6 +639,7 @@ static int __devinit max732x_probe(struct i2c_client *client,
|
|||
return 0;
|
||||
|
||||
out_failed:
|
||||
max732x_irq_teardown(chip);
|
||||
kfree(chip);
|
||||
return ret;
|
||||
}
|
||||
|
|
@ -352,6 +667,8 @@ static int __devexit max732x_remove(struct i2c_client *client)
|
|||
return ret;
|
||||
}
|
||||
|
||||
max732x_irq_teardown(chip);
|
||||
|
||||
/* unregister any dummy i2c_client */
|
||||
if (chip->client_dummy)
|
||||
i2c_unregister_device(chip->client_dummy);
|
||||
|
|
|
|||
|
|
@ -7,6 +7,9 @@ struct max732x_platform_data {
|
|||
/* number of the first GPIO */
|
||||
unsigned gpio_base;
|
||||
|
||||
/* interrupt base */
|
||||
int irq_base;
|
||||
|
||||
void *context; /* param to setup/teardown */
|
||||
|
||||
int (*setup)(struct i2c_client *client,
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue