OpenCloudOS-Kernel/drivers/w1/masters/w1-gpio.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* w1-gpio - GPIO w1 bus master driver
*
* Copyright (C) 2007 Ville Syrjala <syrjala@sci.fi>
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/w1-gpio.h>
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
#include <linux/gpio/consumer.h>
#include <linux/of_platform.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/delay.h>
#include <linux/w1.h>
static u8 w1_gpio_set_pullup(void *data, int delay)
{
struct w1_gpio_platform_data *pdata = data;
if (delay) {
pdata->pullup_duration = delay;
} else {
if (pdata->pullup_duration) {
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
/*
* This will OVERRIDE open drain emulation and force-pull
* the line high for some time.
*/
gpiod_set_raw_value(pdata->gpiod, 1);
msleep(pdata->pullup_duration);
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
/*
* This will simply set the line as input since we are doing
* open drain emulation in the GPIO library.
*/
gpiod_set_value(pdata->gpiod, 1);
}
pdata->pullup_duration = 0;
}
return 0;
}
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
static void w1_gpio_write_bit(void *data, u8 bit)
{
struct w1_gpio_platform_data *pdata = data;
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
gpiod_set_value(pdata->gpiod, bit);
}
static u8 w1_gpio_read_bit(void *data)
{
struct w1_gpio_platform_data *pdata = data;
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
return gpiod_get_value(pdata->gpiod) ? 1 : 0;
}
#if defined(CONFIG_OF)
static const struct of_device_id w1_gpio_dt_ids[] = {
{ .compatible = "w1-gpio" },
{}
};
MODULE_DEVICE_TABLE(of, w1_gpio_dt_ids);
#endif
static int w1_gpio_probe(struct platform_device *pdev)
{
struct w1_bus_master *master;
struct w1_gpio_platform_data *pdata;
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
/* Enforce open drain mode by default */
enum gpiod_flags gflags = GPIOD_OUT_LOW_OPEN_DRAIN;
int err;
if (of_have_populated_dt()) {
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
/*
* This parameter means that something else than the gpiolib has
* already set the line into open drain mode, so we should just
* driver it high/low like we are in full control of the line and
* open drain will happen transparently.
*/
if (of_property_present(np, "linux,open-drain"))
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
gflags = GPIOD_OUT_LOW;
pdev->dev.platform_data = pdata;
}
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
pdata = dev_get_platdata(dev);
if (!pdata) {
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
dev_err(dev, "No configuration data\n");
return -ENXIO;
}
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
master = devm_kzalloc(dev, sizeof(struct w1_bus_master),
GFP_KERNEL);
if (!master)
return -ENOMEM;
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
pdata->gpiod = devm_gpiod_get_index(dev, NULL, 0, gflags);
if (IS_ERR(pdata->gpiod)) {
dev_err(dev, "gpio_request (pin) failed\n");
return PTR_ERR(pdata->gpiod);
}
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
pdata->pullup_gpiod =
devm_gpiod_get_index_optional(dev, NULL, 1, GPIOD_OUT_LOW);
if (IS_ERR(pdata->pullup_gpiod)) {
dev_err(dev, "gpio_request_one "
"(ext_pullup_enable_pin) failed\n");
return PTR_ERR(pdata->pullup_gpiod);
}
master->data = pdata;
master->read_bit = w1_gpio_read_bit;
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
gpiod_direction_output(pdata->gpiod, 1);
master->write_bit = w1_gpio_write_bit;
/*
* If we are using open drain emulation from the GPIO library,
* we need to use this pullup function that hammers the line
* high using a raw accessor to provide pull-up for the w1
* line.
*/
if (gflags == GPIOD_OUT_LOW_OPEN_DRAIN)
master->set_pullup = w1_gpio_set_pullup;
err = w1_add_master_device(master);
if (err) {
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
dev_err(dev, "w1_add_master device failed\n");
return err;
}
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(1);
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
if (pdata->pullup_gpiod)
gpiod_set_value(pdata->pullup_gpiod, 1);
platform_set_drvdata(pdev, master);
return 0;
}
static int w1_gpio_remove(struct platform_device *pdev)
{
struct w1_bus_master *master = platform_get_drvdata(pdev);
struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(0);
w1: w1-gpio: Convert to use GPIO descriptors The w1 master driver includes a complete open drain emulation reimplementation among other things. This converts the driver and all board files using it to use GPIO descriptors associated with the device to look up the GPIO wire, as well ass the optional pull-up GPIO line. When probed from the device tree, the driver will just pick descriptors and use them right off. For the two board files in the kernel, we add descriptor lookups so we do not need to keep any old platform data handling around for the GPIO lines. As the platform data is also a state container for this driver, we augment it to contain the GPIO descriptors. w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone since this pair was a reimplementation of open drain emulation which is now handled by gpiolib. The special "linux,open-drain" flag is a bit of mishap here: it has the same semantic as the same flags in I2C: it means that something in the platform is setting up the line as open drain behind our back. We handle this the same way as in I2C. To drive the pull-up, we need to bypass open drain emulation in gpiolib for the line, and this is done by driving it high using gpiod_set_raw_value() which has been augmented to have the semantic of overriding the open drain emulation. We also augment the documentation to reflect the way to pass GPIO descriptors from the machine. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-27 02:27:09 +08:00
if (pdata->pullup_gpiod)
gpiod_set_value(pdata->pullup_gpiod, 0);
w1_remove_master_device(master);
return 0;
}
static int __maybe_unused w1_gpio_suspend(struct device *dev)
{
struct w1_gpio_platform_data *pdata = dev_get_platdata(dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(0);
return 0;
}
static int __maybe_unused w1_gpio_resume(struct device *dev)
{
struct w1_gpio_platform_data *pdata = dev_get_platdata(dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(1);
return 0;
}
static SIMPLE_DEV_PM_OPS(w1_gpio_pm_ops, w1_gpio_suspend, w1_gpio_resume);
static struct platform_driver w1_gpio_driver = {
.driver = {
.name = "w1-gpio",
.pm = &w1_gpio_pm_ops,
.of_match_table = of_match_ptr(w1_gpio_dt_ids),
},
.probe = w1_gpio_probe,
.remove = w1_gpio_remove,
};
module_platform_driver(w1_gpio_driver);
MODULE_DESCRIPTION("GPIO w1 bus master driver");
MODULE_AUTHOR("Ville Syrjala <syrjala@sci.fi>");
MODULE_LICENSE("GPL");