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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-05 09:51:41 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-05 09:51:41 -0700 |
commit | 1b2951dd99af3970c1c1a8385a12b90236b837de (patch) | |
tree | f0263fd6e22c23078b38360ea7495b1dd2d212dc /drivers/gpio/gpio-raspberrypi-exp.c | |
parent | 06dd3dfeea60e2a6457a6aedf97afc8e6d2ba497 (diff) | |
parent | 348f3cde84ab5b1f53cd3c0eaac1ca99a4dcb148 (diff) | |
download | linux-1b2951dd99af3970c1c1a8385a12b90236b837de.tar.bz2 |
Merge tag 'gpio-v4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v4.17 kernel cycle:
New drivers:
- Nintendo Wii GameCube GPIO, known as "Hollywood"
- Raspberry Pi mailbox service GPIO expander
- Spreadtrum main SC9860 SoC and IEC GPIO controllers.
Improvements:
- Implemented .get_multiple() callback for most of the
high-performance industrial GPIO cards for the ISA bus.
- ISA GPIO drivers now select the ISA_BUS_API instead of depending on
it. This is merged with the same pattern for all the ISA drivers
and some other Kconfig cleanups related to this.
Cleanup:
- Delete the TZ1090 GPIO drivers following the deletion of this SoC
from the ARM tree.
- Move the documentation over to driver-api to conform with the rest
of the kernel documentation build.
- Continue to make the GPIO drivers include only
<linux/gpio/driver.h> and not the too broad <linux/gpio.h> that we
want to get rid of.
- Managed to remove VLA allocation from two drivers pending more
fixes in this area for the next merge window.
- Misc janitorial fixes"
* tag 'gpio-v4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (77 commits)
gpio: Add Spreadtrum PMIC EIC driver support
gpio: Add Spreadtrum EIC driver support
dt-bindings: gpio: Add Spreadtrum EIC controller documentation
gpio: ath79: Fix potential NULL dereference in ath79_gpio_probe()
pinctrl: qcom: Don't allow protected pins to be requested
gpiolib: Support 'gpio-reserved-ranges' property
gpiolib: Change bitmap allocation to kmalloc_array
gpiolib: Extract mask allocation into subroutine
dt-bindings: gpio: Add a gpio-reserved-ranges property
gpio: mockup: fix a potential crash when creating debugfs entries
gpio: pca953x: add compatibility for pcal6524 and pcal9555a
gpio: dwapb: Add support for a bus clock
gpio: Remove VLA from xra1403 driver
gpio: Remove VLA from MAX3191X driver
gpio: ws16c48: Implement get_multiple callback
gpio: gpio-mm: Implement get_multiple callback
gpio: 104-idi-48: Implement get_multiple callback
gpio: 104-dio-48e: Implement get_multiple callback
gpio: pcie-idio-24: Implement get_multiple/set_multiple callbacks
gpio: pci-idio-16: Implement get_multiple callback
...
Diffstat (limited to 'drivers/gpio/gpio-raspberrypi-exp.c')
-rw-r--r-- | drivers/gpio/gpio-raspberrypi-exp.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-raspberrypi-exp.c b/drivers/gpio/gpio-raspberrypi-exp.c new file mode 100644 index 000000000000..d6d36d537e37 --- /dev/null +++ b/drivers/gpio/gpio-raspberrypi-exp.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Raspberry Pi 3 expander GPIO driver + * + * Uses the firmware mailbox service to communicate with the + * GPIO expander on the VPU. + * + * Copyright (C) 2017 Raspberry Pi Trading Ltd. + */ + +#include <linux/err.h> +#include <linux/gpio/driver.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <soc/bcm2835/raspberrypi-firmware.h> + +#define MODULE_NAME "raspberrypi-exp-gpio" +#define NUM_GPIO 8 + +#define RPI_EXP_GPIO_BASE 128 + +#define RPI_EXP_GPIO_DIR_IN 0 +#define RPI_EXP_GPIO_DIR_OUT 1 + +struct rpi_exp_gpio { + struct gpio_chip gc; + struct rpi_firmware *fw; +}; + +/* VC4 firmware mailbox interface data structures */ + +struct gpio_set_config { + u32 gpio; + u32 direction; + u32 polarity; + u32 term_en; + u32 term_pull_up; + u32 state; +}; + +struct gpio_get_config { + u32 gpio; + u32 direction; + u32 polarity; + u32 term_en; + u32 term_pull_up; +}; + +struct gpio_get_set_state { + u32 gpio; + u32 state; +}; + +static int rpi_exp_gpio_get_polarity(struct gpio_chip *gc, unsigned int off) +{ + struct rpi_exp_gpio *gpio; + struct gpio_get_config get; + int ret; + + gpio = gpiochip_get_data(gc); + + get.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG, + &get, sizeof(get)); + if (ret || get.gpio != 0) { + dev_err(gc->parent, "Failed to get GPIO %u config (%d %x)\n", + off, ret, get.gpio); + return ret ? ret : -EIO; + } + return get.polarity; +} + +static int rpi_exp_gpio_dir_in(struct gpio_chip *gc, unsigned int off) +{ + struct rpi_exp_gpio *gpio; + struct gpio_set_config set_in; + int ret; + + gpio = gpiochip_get_data(gc); + + set_in.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + set_in.direction = RPI_EXP_GPIO_DIR_IN; + set_in.term_en = 0; /* termination disabled */ + set_in.term_pull_up = 0; /* n/a as termination disabled */ + set_in.state = 0; /* n/a as configured as an input */ + + ret = rpi_exp_gpio_get_polarity(gc, off); + if (ret < 0) + return ret; + set_in.polarity = ret; /* Retain existing setting */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG, + &set_in, sizeof(set_in)); + if (ret || set_in.gpio != 0) { + dev_err(gc->parent, "Failed to set GPIO %u to input (%d %x)\n", + off, ret, set_in.gpio); + return ret ? ret : -EIO; + } + return 0; +} + +static int rpi_exp_gpio_dir_out(struct gpio_chip *gc, unsigned int off, int val) +{ + struct rpi_exp_gpio *gpio; + struct gpio_set_config set_out; + int ret; + + gpio = gpiochip_get_data(gc); + + set_out.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + set_out.direction = RPI_EXP_GPIO_DIR_OUT; + set_out.term_en = 0; /* n/a as an output */ + set_out.term_pull_up = 0; /* n/a as termination disabled */ + set_out.state = val; /* Output state */ + + ret = rpi_exp_gpio_get_polarity(gc, off); + if (ret < 0) + return ret; + set_out.polarity = ret; /* Retain existing setting */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG, + &set_out, sizeof(set_out)); + if (ret || set_out.gpio != 0) { + dev_err(gc->parent, "Failed to set GPIO %u to output (%d %x)\n", + off, ret, set_out.gpio); + return ret ? ret : -EIO; + } + return 0; +} + +static int rpi_exp_gpio_get_direction(struct gpio_chip *gc, unsigned int off) +{ + struct rpi_exp_gpio *gpio; + struct gpio_get_config get; + int ret; + + gpio = gpiochip_get_data(gc); + + get.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG, + &get, sizeof(get)); + if (ret || get.gpio != 0) { + dev_err(gc->parent, + "Failed to get GPIO %u config (%d %x)\n", off, ret, + get.gpio); + return ret ? ret : -EIO; + } + return !get.direction; +} + +static int rpi_exp_gpio_get(struct gpio_chip *gc, unsigned int off) +{ + struct rpi_exp_gpio *gpio; + struct gpio_get_set_state get; + int ret; + + gpio = gpiochip_get_data(gc); + + get.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + get.state = 0; /* storage for returned value */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_STATE, + &get, sizeof(get)); + if (ret || get.gpio != 0) { + dev_err(gc->parent, + "Failed to get GPIO %u state (%d %x)\n", off, ret, + get.gpio); + return ret ? ret : -EIO; + } + return !!get.state; +} + +static void rpi_exp_gpio_set(struct gpio_chip *gc, unsigned int off, int val) +{ + struct rpi_exp_gpio *gpio; + struct gpio_get_set_state set; + int ret; + + gpio = gpiochip_get_data(gc); + + set.gpio = off + RPI_EXP_GPIO_BASE; /* GPIO to update */ + set.state = val; /* Output state */ + + ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_STATE, + &set, sizeof(set)); + if (ret || set.gpio != 0) + dev_err(gc->parent, + "Failed to set GPIO %u state (%d %x)\n", off, ret, + set.gpio); +} + +static int rpi_exp_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *fw_node; + struct rpi_firmware *fw; + struct rpi_exp_gpio *rpi_gpio; + + fw_node = of_get_parent(np); + if (!fw_node) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + fw = rpi_firmware_get(fw_node); + if (!fw) + return -EPROBE_DEFER; + + rpi_gpio = devm_kzalloc(dev, sizeof(*rpi_gpio), GFP_KERNEL); + if (!rpi_gpio) + return -ENOMEM; + + rpi_gpio->fw = fw; + rpi_gpio->gc.parent = dev; + rpi_gpio->gc.label = MODULE_NAME; + rpi_gpio->gc.owner = THIS_MODULE; + rpi_gpio->gc.of_node = np; + rpi_gpio->gc.base = -1; + rpi_gpio->gc.ngpio = NUM_GPIO; + + rpi_gpio->gc.direction_input = rpi_exp_gpio_dir_in; + rpi_gpio->gc.direction_output = rpi_exp_gpio_dir_out; + rpi_gpio->gc.get_direction = rpi_exp_gpio_get_direction; + rpi_gpio->gc.get = rpi_exp_gpio_get; + rpi_gpio->gc.set = rpi_exp_gpio_set; + rpi_gpio->gc.can_sleep = true; + + return devm_gpiochip_add_data(dev, &rpi_gpio->gc, rpi_gpio); +} + +static const struct of_device_id rpi_exp_gpio_ids[] = { + { .compatible = "raspberrypi,firmware-gpio" }, + { } +}; +MODULE_DEVICE_TABLE(of, rpi_exp_gpio_ids); + +static struct platform_driver rpi_exp_gpio_driver = { + .driver = { + .name = MODULE_NAME, + .of_match_table = of_match_ptr(rpi_exp_gpio_ids), + }, + .probe = rpi_exp_gpio_probe, +}; +module_platform_driver(rpi_exp_gpio_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Dave Stevenson <dave.stevenson@raspberrypi.org>"); +MODULE_DESCRIPTION("Raspberry Pi 3 expander GPIO driver"); +MODULE_ALIAS("platform:rpi-exp-gpio"); |