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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-15 21:10:39 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-15 21:10:39 -0700 |
commit | 273cbf61c3ddee9574ef1f4959b9bc6db5b24271 (patch) | |
tree | 1eb8a54d416453ad7c6adbf57ab05dce2587a012 /drivers/i2c/muxes/i2c-arb-gpio-challenge.c | |
parent | 5fe7b600a116187e10317d83fb56922c4ef6b76d (diff) | |
parent | cc6b9dfb2c5769afeb3335048173c730bdf8dbe1 (diff) | |
download | linux-273cbf61c3ddee9574ef1f4959b9bc6db5b24271.tar.bz2 |
Merge branch 'i2c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
"New stuff from the I2C world:
- in the core, getting irqs from ACPI is now similar to OF
- new driver for MediaTek MT7621/7628/7688 SoCs
- bcm2835, i801, and tegra drivers got some more attention
- GPIO API cleanups
- cleanups in the core headers
- lots of usual driver updates"
* 'i2c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (74 commits)
i2c: mt7621: Fix platform_no_drv_owner.cocci warnings
i2c: cpm: remove casting dma_alloc
dt-bindings: i2c: sun6i-p2wi: Fix the binding example
dt-bindings: i2c: mv64xxx: Fix the example compatible
i2c: i801: Documentation update
i2c: i801: Add support for Intel Tiger Lake
i2c: i801: Fix PCI ID sorting
dt-bindings: i2c-stm32: document optional dmas
i2c: i2c-stm32f7: Add I2C_SMBUS_I2C_BLOCK_DATA support
i2c: core: Tidy up handling of init_irq
i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
i2c: core: Move ACPI IRQ handling to probe time
i2c: acpi: Factor out getting the IRQ from ACPI
i2c: acpi: Use available IRQ helper functions
i2c: core: Allow whole core to use i2c_dev_irq_from_resources
eeprom: at24: modify a comment referring to platform data
dt-bindings: i2c: omap: Add new compatible for J721E SoCs
dt-bindings: i2c: mv64xxx: Add YAML schemas
dt-bindings: i2c: sun6i-p2wi: Add YAML schemas
i2c: mt7621: Add MediaTek MT7621/7628/7688 I2C driver
...
Diffstat (limited to 'drivers/i2c/muxes/i2c-arb-gpio-challenge.c')
-rw-r--r-- | drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 79 |
1 files changed, 27 insertions, 52 deletions
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c index 255c598dcfc8..6dc88902c189 100644 --- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c +++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c @@ -6,12 +6,11 @@ */ #include <linux/delay.h> -#include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/kernel.h> #include <linux/i2c.h> #include <linux/i2c-mux.h> #include <linux/module.h> -#include <linux/of_gpio.h> #include <linux/platform_device.h> #include <linux/slab.h> @@ -19,22 +18,16 @@ /** * struct i2c_arbitrator_data - Driver data for I2C arbitrator * - * @our_gpio: GPIO we'll use to claim. - * @our_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO == - * this then consider it released. - * @their_gpio: GPIO that the other side will use to claim. - * @their_gpio_release: 0 if active high; 1 if active low; AKA if the GPIO == - * this then consider it released. + * @our_gpio: GPIO descriptor we'll use to claim. + * @their_gpio: GPIO descriptor that the other side will use to claim. * @slew_delay_us: microseconds to wait for a GPIO to go high. * @wait_retry_us: we'll attempt another claim after this many microseconds. * @wait_free_us: we'll give up after this many microseconds. */ struct i2c_arbitrator_data { - int our_gpio; - int our_gpio_release; - int their_gpio; - int their_gpio_release; + struct gpio_desc *our_gpio; + struct gpio_desc *their_gpio; unsigned int slew_delay_us; unsigned int wait_retry_us; unsigned int wait_free_us; @@ -55,15 +48,15 @@ static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan) stop_time = jiffies + usecs_to_jiffies(arb->wait_free_us) + 1; do { /* Indicate that we want to claim the bus */ - gpio_set_value(arb->our_gpio, !arb->our_gpio_release); + gpiod_set_value(arb->our_gpio, 1); udelay(arb->slew_delay_us); /* Wait for the other master to release it */ stop_retry = jiffies + usecs_to_jiffies(arb->wait_retry_us) + 1; while (time_before(jiffies, stop_retry)) { - int gpio_val = !!gpio_get_value(arb->their_gpio); + int gpio_val = gpiod_get_value(arb->their_gpio); - if (gpio_val == arb->their_gpio_release) { + if (!gpio_val) { /* We got it, so return */ return 0; } @@ -72,13 +65,13 @@ static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan) } /* It didn't release, so give up, wait, and try again */ - gpio_set_value(arb->our_gpio, arb->our_gpio_release); + gpiod_set_value(arb->our_gpio, 0); usleep_range(arb->wait_retry_us, arb->wait_retry_us * 2); } while (time_before(jiffies, stop_time)); /* Give up, release our claim */ - gpio_set_value(arb->our_gpio, arb->our_gpio_release); + gpiod_set_value(arb->our_gpio, 0); udelay(arb->slew_delay_us); dev_err(muxc->dev, "Could not claim bus, timeout\n"); return -EBUSY; @@ -94,7 +87,7 @@ static int i2c_arbitrator_deselect(struct i2c_mux_core *muxc, u32 chan) const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc); /* Release the bus and wait for the other master to notice */ - gpio_set_value(arb->our_gpio, arb->our_gpio_release); + gpiod_set_value(arb->our_gpio, 0); udelay(arb->slew_delay_us); return 0; @@ -107,8 +100,7 @@ static int i2c_arbitrator_probe(struct platform_device *pdev) struct device_node *parent_np; struct i2c_mux_core *muxc; struct i2c_arbitrator_data *arb; - enum of_gpio_flags gpio_flags; - unsigned long out_init; + struct gpio_desc *dummy; int ret; /* We only support probing from device tree; no platform_data */ @@ -129,45 +121,28 @@ static int i2c_arbitrator_probe(struct platform_device *pdev) platform_set_drvdata(pdev, muxc); - /* Request GPIOs */ - ret = of_get_named_gpio_flags(np, "our-claim-gpio", 0, &gpio_flags); - if (!gpio_is_valid(ret)) { - if (ret != -EPROBE_DEFER) - dev_err(dev, "Error getting our-claim-gpio\n"); - return ret; - } - arb->our_gpio = ret; - arb->our_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW); - out_init = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? - GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW; - ret = devm_gpio_request_one(dev, arb->our_gpio, out_init, - "our-claim-gpio"); - if (ret) { - if (ret != -EPROBE_DEFER) - dev_err(dev, "Error requesting our-claim-gpio\n"); - return ret; + /* Request GPIOs, our GPIO as unclaimed to begin with */ + arb->our_gpio = devm_gpiod_get(dev, "our-claim", GPIOD_OUT_LOW); + if (IS_ERR(arb->our_gpio)) { + dev_err(dev, "could not get \"our-claim\" GPIO (%ld)\n", + PTR_ERR(arb->our_gpio)); + return PTR_ERR(arb->our_gpio); } - ret = of_get_named_gpio_flags(np, "their-claim-gpios", 0, &gpio_flags); - if (!gpio_is_valid(ret)) { - if (ret != -EPROBE_DEFER) - dev_err(dev, "Error getting their-claim-gpio\n"); - return ret; - } - arb->their_gpio = ret; - arb->their_gpio_release = !!(gpio_flags & OF_GPIO_ACTIVE_LOW); - ret = devm_gpio_request_one(dev, arb->their_gpio, GPIOF_IN, - "their-claim-gpio"); - if (ret) { - if (ret != -EPROBE_DEFER) - dev_err(dev, "Error requesting their-claim-gpio\n"); - return ret; + arb->their_gpio = devm_gpiod_get(dev, "their-claim", GPIOD_IN); + if (IS_ERR(arb->their_gpio)) { + dev_err(dev, "could not get \"their-claim\" GPIO (%ld)\n", + PTR_ERR(arb->their_gpio)); + return PTR_ERR(arb->their_gpio); } /* At the moment we only support a single two master (us + 1 other) */ - if (gpio_is_valid(of_get_named_gpio(np, "their-claim-gpios", 1))) { + dummy = devm_gpiod_get_index(dev, "their-claim", 1, GPIOD_IN); + if (!IS_ERR(dummy)) { dev_err(dev, "Only one other master is supported\n"); return -EINVAL; + } else if (PTR_ERR(dummy) == -EPROBE_DEFER) { + return -EPROBE_DEFER; } /* Arbitration parameters */ |