diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-13 10:09:33 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-10-13 10:09:33 -0700 |
commit | 0486beaf88d2460e9dbcbba281dab683a838f0c6 (patch) | |
tree | b52d063e60c23daa6332c4382b050b6094ac9b78 /tools/gpio/gpio-utils.c | |
parent | a996b9c61729cd1507e48303c214dc317df890e2 (diff) | |
parent | fc709df553a34fd18010f52e6b47652268d83e7d (diff) |
Merge tag 'gpio-v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"This time very little driver changes but lots of core changes.
We have some interesting cooperative work for ARM and Intel alike,
making the GPIO subsystem more and more suitable for industrial
systems and the like, in addition to the in-kernel users.
We touch driver core (device properties) and lib/* by adding one
simple string array free function, these are authored by Andy
Shevchenko who is a well known and recognized core helpers maintainers
so this should be fine.
We also see some Android GKI-related modularization in the MXC
drivers.
Core changes:
- The big core change is the updated (v2) userspace character device
API.
This corrects badly designed 64-bit alignment around the line
events. We also add the debounce request feature. This echoes the
often quotes passage from Frederick Brooks "The mythical man-month"
to always throw one away, which we have seen before in things such
as V4L2. So we put in a new one and deprecate and obsolete the old
one.
- All example tools in tools/gpio/* are migrated to the new API to
set a good example. The libgpiod userspace library has been
augmented to use this new API pretty much from day 1.
- Some misc API hardening by using strn* function calls has been
added as well.
- Use the simpler IDA interface for GPIO chip instance enumeration.
- Add device core function for counting string arrays in device
properties.
- Provide a generic library function kfree_strarray() that can be
used throughout the kernel.
Driver enhancements:
- The DesignWare dwapb-gpio driver has been enhanced and now uses the
IRQ handling in the gpiolib core.
- The mockup and aggregator drivers have seen some substantial code
clean-up and now use more of the core kernel inftrastructure.
- Misc cleanups using dev_err_probe().
- The MXC drivers (Freescale/NXP) can now be built modularized, which
makes modularized GKI Android kernels happy"
* tag 'gpio-v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (73 commits)
gpiolib: Update header block in gpiolib-cdev.h
gpiolib: cdev: switch from kstrdup() to kstrndup()
docs: gpio: add a new document to its index.rst
gpio: pca953x: Add support for the NXP PCAL9554B/C
tools: gpio: add debounce support to gpio-event-mon
tools: gpio: add multi-line monitoring to gpio-event-mon
tools: gpio: port gpio-event-mon to v2 uAPI
tools: gpio: port gpio-hammer to v2 uAPI
tools: gpio: rename nlines to num_lines
tools: gpio: port gpio-watch to v2 uAPI
tools: gpio: port lsgpio to v2 uAPI
gpio: uapi: document uAPI v1 as deprecated
gpiolib: cdev: support setting debounce
gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL
gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL
gpiolib: cdev: support edge detection for uAPI v2
gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL
gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL
gpiolib: add build option for CDEV v1 ABI
gpiolib: make cdev a build option
...
Diffstat (limited to 'tools/gpio/gpio-utils.c')
-rw-r--r-- | tools/gpio/gpio-utils.c | 176 |
1 files changed, 141 insertions, 35 deletions
diff --git a/tools/gpio/gpio-utils.c b/tools/gpio/gpio-utils.c index 16a5d9cb9da2..37187e056c8b 100644 --- a/tools/gpio/gpio-utils.c +++ b/tools/gpio/gpio-utils.c @@ -38,7 +38,7 @@ * such as "gpiochip0" * @lines: An array desired lines, specified by offset * index for the associated GPIO device. - * @nline: The number of lines to request. + * @num_lines: The number of lines to request. * @flag: The new flag for requsted gpio. Reference * "linux/gpio.h" for the meaning of flag. * @data: Default value will be set to gpio when flag is @@ -56,7 +56,7 @@ * On failure return the errno. */ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines, - unsigned int nlines, unsigned int flag, + unsigned int num_lines, unsigned int flag, struct gpiohandle_data *data, const char *consumer_label) { @@ -78,12 +78,12 @@ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines, goto exit_free_name; } - for (i = 0; i < nlines; i++) + for (i = 0; i < num_lines; i++) req.lineoffsets[i] = lines[i]; req.flags = flag; strcpy(req.consumer_label, consumer_label); - req.lines = nlines; + req.lines = num_lines; if (flag & GPIOHANDLE_REQUEST_OUTPUT) memcpy(req.default_values, data, sizeof(req.default_values)); @@ -100,20 +100,87 @@ exit_free_name: free(chrdev_name); return ret < 0 ? ret : req.fd; } + +/** + * gpiotools_request_line() - request gpio lines in a gpiochip + * @device_name: The name of gpiochip without prefix "/dev/", + * such as "gpiochip0" + * @lines: An array desired lines, specified by offset + * index for the associated GPIO device. + * @num_lines: The number of lines to request. + * @config: The new config for requested gpio. Reference + * "linux/gpio.h" for config details. + * @consumer: The name of consumer, such as "sysfs", + * "powerkey". This is useful for other users to + * know who is using. + * + * Request gpio lines through the ioctl provided by chardev. User + * could call gpiotools_set_values() and gpiotools_get_values() to + * read and write respectively through the returned fd. Call + * gpiotools_release_line() to release these lines after that. + * + * Return: On success return the fd; + * On failure return the errno. + */ +int gpiotools_request_line(const char *device_name, unsigned int *lines, + unsigned int num_lines, + struct gpio_v2_line_config *config, + const char *consumer) +{ + struct gpio_v2_line_request req; + char *chrdev_name; + int fd; + int i; + int ret; + + ret = asprintf(&chrdev_name, "/dev/%s", device_name); + if (ret < 0) + return -ENOMEM; + + fd = open(chrdev_name, 0); + if (fd == -1) { + ret = -errno; + fprintf(stderr, "Failed to open %s, %s\n", + chrdev_name, strerror(errno)); + goto exit_free_name; + } + + memset(&req, 0, sizeof(req)); + for (i = 0; i < num_lines; i++) + req.offsets[i] = lines[i]; + + req.config = *config; + strcpy(req.consumer, consumer); + req.num_lines = num_lines; + + ret = ioctl(fd, GPIO_V2_GET_LINE_IOCTL, &req); + if (ret == -1) { + ret = -errno; + fprintf(stderr, "Failed to issue %s (%d), %s\n", + "GPIO_GET_LINE_IOCTL", ret, strerror(errno)); + } + + if (close(fd) == -1) + perror("Failed to close GPIO character device file"); +exit_free_name: + free(chrdev_name); + return ret < 0 ? ret : req.fd; +} + /** * gpiotools_set_values(): Set the value of gpio(s) * @fd: The fd returned by - * gpiotools_request_linehandle(). - * @data: The array of values want to set. + * gpiotools_request_line(). + * @values: The array of values want to set. * * Return: On success return 0; * On failure return the errno. */ -int gpiotools_set_values(const int fd, struct gpiohandle_data *data) +int gpiotools_set_values(const int fd, struct gpio_v2_line_values *values) { int ret; - ret = ioctl(fd, GPIOHANDLE_SET_LINE_VALUES_IOCTL, data); + ret = ioctl(fd, GPIO_V2_LINE_SET_VALUES_IOCTL, values); if (ret == -1) { ret = -errno; fprintf(stderr, "Failed to issue %s (%d), %s\n", @@ -127,17 +194,17 @@ int gpiotools_set_values(const int fd, struct gpiohandle_data *data) /** * gpiotools_get_values(): Get the value of gpio(s) * @fd: The fd returned by - * gpiotools_request_linehandle(). - * @data: The array of values get from hardware. + * gpiotools_request_line(). + * @values: The array of values get from hardware. * * Return: On success return 0; * On failure return the errno. */ -int gpiotools_get_values(const int fd, struct gpiohandle_data *data) +int gpiotools_get_values(const int fd, struct gpio_v2_line_values *values) { int ret; - ret = ioctl(fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, data); + ret = ioctl(fd, GPIO_V2_LINE_GET_VALUES_IOCTL, values); if (ret == -1) { ret = -errno; fprintf(stderr, "Failed to issue %s (%d), %s\n", @@ -170,6 +237,27 @@ int gpiotools_release_linehandle(const int fd) } /** + * gpiotools_release_line(): Release the line(s) of gpiochip + * @fd: The fd returned by + * gpiotools_request_line(). + * + * Return: On success return 0; + * On failure return the errno. + */ +int gpiotools_release_line(const int fd) +{ + int ret; + + ret = close(fd); + if (ret == -1) { + perror("Failed to close GPIO LINE device file"); + ret = -errno; + } + + return ret; +} + +/** * gpiotools_get(): Get value from specific line * @device_name: The name of gpiochip without prefix "/dev/", * such as "gpiochip0" @@ -180,11 +268,14 @@ int gpiotools_release_linehandle(const int fd) */ int gpiotools_get(const char *device_name, unsigned int line) { - struct gpiohandle_data data; + int ret; + unsigned int value; unsigned int lines[] = {line}; - gpiotools_gets(device_name, lines, 1, &data); - return data.values[0]; + ret = gpiotools_gets(device_name, lines, 1, &value); + if (ret) + return ret; + return value; } @@ -194,28 +285,36 @@ int gpiotools_get(const char *device_name, unsigned int line) * such as "gpiochip0". * @lines: An array desired lines, specified by offset * index for the associated GPIO device. - * @nline: The number of lines to request. - * @data: The array of values get from gpiochip. + * @num_lines: The number of lines to request. + * @values: The array of values get from gpiochip. * * Return: On success return 0; * On failure return the errno. */ int gpiotools_gets(const char *device_name, unsigned int *lines, - unsigned int nlines, struct gpiohandle_data *data) + unsigned int num_lines, unsigned int *values) { - int fd; + int fd, i; int ret; int ret_close; + struct gpio_v2_line_config config; + struct gpio_v2_line_values lv; - ret = gpiotools_request_linehandle(device_name, lines, nlines, - GPIOHANDLE_REQUEST_INPUT, data, - CONSUMER); + memset(&config, 0, sizeof(config)); + config.flags = GPIO_V2_LINE_FLAG_INPUT; + ret = gpiotools_request_line(device_name, lines, num_lines, + &config, CONSUMER); if (ret < 0) return ret; fd = ret; - ret = gpiotools_get_values(fd, data); - ret_close = gpiotools_release_linehandle(fd); + for (i = 0; i < num_lines; i++) + gpiotools_set_bit(&lv.mask, i); + ret = gpiotools_get_values(fd, &lv); + if (!ret) + for (i = 0; i < num_lines; i++) + values[i] = gpiotools_test_bit(lv.bits, i); + ret_close = gpiotools_release_line(fd); return ret < 0 ? ret : ret_close; } @@ -232,11 +331,9 @@ int gpiotools_gets(const char *device_name, unsigned int *lines, int gpiotools_set(const char *device_name, unsigned int line, unsigned int value) { - struct gpiohandle_data data; unsigned int lines[] = {line}; - data.values[0] = value; - return gpiotools_sets(device_name, lines, 1, &data); + return gpiotools_sets(device_name, lines, 1, &value); } /** @@ -245,23 +342,32 @@ int gpiotools_set(const char *device_name, unsigned int line, * such as "gpiochip0". * @lines: An array desired lines, specified by offset * index for the associated GPIO device. - * @nline: The number of lines to request. - * @data: The array of values set to gpiochip, must be + * @num_lines: The number of lines to request. + * @value: The array of values set to gpiochip, must be * 0(low) or 1(high). * * Return: On success return 0; * On failure return the errno. */ int gpiotools_sets(const char *device_name, unsigned int *lines, - unsigned int nlines, struct gpiohandle_data *data) + unsigned int num_lines, unsigned int *values) { - int ret; + int ret, i; + struct gpio_v2_line_config config; - ret = gpiotools_request_linehandle(device_name, lines, nlines, - GPIOHANDLE_REQUEST_OUTPUT, data, - CONSUMER); + memset(&config, 0, sizeof(config)); + config.flags = GPIO_V2_LINE_FLAG_OUTPUT; + config.num_attrs = 1; + config.attrs[0].attr.id = GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES; + for (i = 0; i < num_lines; i++) { + gpiotools_set_bit(&config.attrs[0].mask, i); + gpiotools_assign_bit(&config.attrs[0].attr.values, + i, values[i]); + } + ret = gpiotools_request_line(device_name, lines, num_lines, + &config, CONSUMER); if (ret < 0) return ret; - return gpiotools_release_linehandle(ret); + return gpiotools_release_line(ret); } |