[PATCH v7 17/20] tools: gpio: port gpio-hammer to v2 uAPI

From: Kent Gibson
Date: Sat Sep 05 2020 - 09:48:19 EST


Port the gpio-hammer tool to the latest GPIO uAPI.

Signed-off-by: Kent Gibson <warthog618@xxxxxxxxx>
---
tools/gpio/gpio-hammer.c | 32 +++++---
tools/gpio/gpio-utils.c | 164 ++++++++++++++++++++++++++++++++-------
tools/gpio/gpio-utils.h | 46 ++++++++++-
3 files changed, 197 insertions(+), 45 deletions(-)

diff --git a/tools/gpio/gpio-hammer.c b/tools/gpio/gpio-hammer.c
index a2c7577fad5c..54fdf59dd320 100644
--- a/tools/gpio/gpio-hammer.c
+++ b/tools/gpio/gpio-hammer.c
@@ -25,23 +25,30 @@
int hammer_device(const char *device_name, unsigned int *lines, int num_lines,
unsigned int loops)
{
- struct gpiohandle_data data;
+ struct gpio_v2_line_values values;
+ struct gpio_v2_line_config config;
char swirr[] = "-\\|/";
int fd;
int ret;
int i, j;
unsigned int iteration = 0;

- memset(&data.values, 0, sizeof(data.values));
- ret = gpiotools_request_linehandle(device_name, lines, num_lines,
- GPIOHANDLE_REQUEST_OUTPUT, &data,
- "gpio-hammer");
+ memset(&config, 0, sizeof(config));
+ config.flags = GPIO_V2_LINE_FLAG_OUTPUT;
+
+ ret = gpiotools_request_line(device_name, lines, num_lines,
+ &config, "gpio-hammer");
if (ret < 0)
goto exit_error;
else
fd = ret;

- ret = gpiotools_get_values(fd, &data);
+ values.mask = 0;
+ values.bits = 0;
+ for (i = 0; i < num_lines; i++)
+ gpiotools_set_bit(&values.mask, i);
+
+ ret = gpiotools_get_values(fd, &values);
if (ret < 0)
goto exit_close_error;

@@ -53,7 +60,7 @@ int hammer_device(const char *device_name, unsigned int *lines, int num_lines,
}
fprintf(stdout, "] on %s, initial states: [", device_name);
for (i = 0; i < num_lines; i++) {
- fprintf(stdout, "%d", data.values[i]);
+ fprintf(stdout, "%d", gpiotools_test_bit(values.bits, i));
if (i != (num_lines - 1))
fprintf(stdout, ", ");
}
@@ -64,14 +71,14 @@ int hammer_device(const char *device_name, unsigned int *lines, int num_lines,
while (1) {
/* Invert all lines so we blink */
for (i = 0; i < num_lines; i++)
- data.values[i] = !data.values[i];
+ gpiotools_change_bit(&values.bits, i);

- ret = gpiotools_set_values(fd, &data);
+ ret = gpiotools_set_values(fd, &values);
if (ret < 0)
goto exit_close_error;

/* Re-read values to get status */
- ret = gpiotools_get_values(fd, &data);
+ ret = gpiotools_get_values(fd, &values);
if (ret < 0)
goto exit_close_error;

@@ -82,7 +89,8 @@ int hammer_device(const char *device_name, unsigned int *lines, int num_lines,

fprintf(stdout, "[");
for (i = 0; i < num_lines; i++) {
- fprintf(stdout, "%d: %d", lines[i], data.values[i]);
+ fprintf(stdout, "%d: %d", lines[i],
+ gpiotools_test_bit(values.bits, i));
if (i != (num_lines - 1))
fprintf(stdout, ", ");
}
@@ -97,7 +105,7 @@ int hammer_device(const char *device_name, unsigned int *lines, int num_lines,
ret = 0;

exit_close_error:
- gpiotools_release_linehandle(fd);
+ gpiotools_release_line(fd);
exit_error:
return ret;
}
diff --git a/tools/gpio/gpio-utils.c b/tools/gpio/gpio-utils.c
index d527980bcb94..37187e056c8b 100644
--- a/tools/gpio/gpio-utils.c
+++ b/tools/gpio/gpio-utils.c
@@ -100,20 +100,87 @@ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
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",
@@ -169,6 +236,27 @@ int gpiotools_release_linehandle(const int fd)
return ret;
}

+/**
+ * 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/",
@@ -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;
}


@@ -195,27 +286,35 @@ int gpiotools_get(const char *device_name, unsigned int line)
* @lines: An array desired lines, specified by offset
* index for the associated GPIO device.
* @num_lines: The number of lines to request.
- * @data: The array of values get from gpiochip.
+ * @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 num_lines, 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, num_lines,
- 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);
}

/**
@@ -246,22 +343,31 @@ int gpiotools_set(const char *device_name, unsigned int line,
* @lines: An array desired lines, specified by offset
* index for the associated GPIO device.
* @num_lines: The number of lines to request.
- * @data: The array of values set to gpiochip, must be
+ * @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 num_lines, 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, num_lines,
- 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);
}
diff --git a/tools/gpio/gpio-utils.h b/tools/gpio/gpio-utils.h
index 324729577865..f8ea4fac14d5 100644
--- a/tools/gpio/gpio-utils.h
+++ b/tools/gpio/gpio-utils.h
@@ -12,7 +12,9 @@
#ifndef _GPIO_UTILS_H_
#define _GPIO_UTILS_H_

+#include <stdbool.h>
#include <string.h>
+#include <linux/types.h>

#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))

@@ -26,16 +28,52 @@ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
unsigned int num_lines, unsigned int flag,
struct gpiohandle_data *data,
const char *consumer_label);
-int gpiotools_set_values(const int fd, struct gpiohandle_data *data);
-int gpiotools_get_values(const int fd, struct gpiohandle_data *data);
int gpiotools_release_linehandle(const int fd);

+int gpiotools_request_line(const char *device_name,
+ unsigned int *lines,
+ unsigned int num_lines,
+ struct gpio_v2_line_config *config,
+ const char *consumer);
+int gpiotools_set_values(const int fd, struct gpio_v2_line_values *values);
+int gpiotools_get_values(const int fd, struct gpio_v2_line_values *values);
+int gpiotools_release_line(const int fd);
+
int gpiotools_get(const char *device_name, unsigned int line);
int gpiotools_gets(const char *device_name, unsigned int *lines,
- unsigned int num_lines, struct gpiohandle_data *data);
+ unsigned int num_lines, unsigned int *values);
int gpiotools_set(const char *device_name, unsigned int line,
unsigned int value);
int gpiotools_sets(const char *device_name, unsigned int *lines,
- unsigned int num_lines, struct gpiohandle_data *data);
+ unsigned int num_lines, unsigned int *values);
+
+/* helper functions for gpio_v2_line_values bits */
+static inline void gpiotools_set_bit(__u64 *b, int n)
+{
+ *b |= 1ULL << n;
+}
+
+static inline void gpiotools_change_bit(__u64 *b, int n)
+{
+ *b ^= 1ULL << n;
+}
+
+static inline void gpiotools_clear_bit(__u64 *b, int n)
+{
+ *b &= ~(1ULL << n);
+}
+
+static inline int gpiotools_test_bit(__u64 b, int n)
+{
+ return !!(b & 1ULL << n);
+}
+
+static inline void gpiotools_assign_bit(__u64 *b, int n, bool value)
+{
+ if (value)
+ gpiotools_set_bit(b, n);
+ else
+ gpiotools_clear_bit(b, n);
+}

#endif /* _GPIO_UTILS_H_ */
--
2.28.0