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author | William Breathitt Gray <william.gray@linaro.org> | 2022-09-27 18:53:38 -0400 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-09-30 14:32:35 +0200 |
commit | 650ae67bbf7ba5ac193f053969612fbb93247b64 (patch) | |
tree | bf80c0c98c877ded950722bbb4001d9d264ebb54 /drivers/counter/counter-sysfs.c | |
parent | 7bbf842cdcff30ddd1da4ab9059cf92f9d1a4326 (diff) | |
download | lwn-650ae67bbf7ba5ac193f053969612fbb93247b64.tar.gz lwn-650ae67bbf7ba5ac193f053969612fbb93247b64.zip |
counter: Introduce the Signal polarity component
The Signal polarity component represents the active level of a
respective Signal. There are two possible states: positive (rising edge)
and negative (falling edge); enum counter_signal_polarity represents
these states. A convenience macro COUNTER_COMP_POLARITY() is provided
for driver authors to declare a Signal polarity component.
Cc: Julien Panis <jpanis@baylibre.com>
Link: https://lore.kernel.org/r/8f47d6e1db71a11bb1e2666f8e2a6e9d256d4131.1664204990.git.william.gray@linaro.org/
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/b6e53438badcb6318997d13dd2fc052f97d808ac.1664318353.git.william.gray@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/counter/counter-sysfs.c')
-rw-r--r-- | drivers/counter/counter-sysfs.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/counter/counter-sysfs.c b/drivers/counter/counter-sysfs.c index 04eac41dad33..e5dd36e1a45f 100644 --- a/drivers/counter/counter-sysfs.c +++ b/drivers/counter/counter-sysfs.c @@ -91,6 +91,11 @@ static const char *const counter_count_mode_str[] = { [COUNTER_COUNT_MODE_MODULO_N] = "modulo-n" }; +static const char *const counter_signal_polarity_str[] = { + [COUNTER_SIGNAL_POLARITY_POSITIVE] = "positive", + [COUNTER_SIGNAL_POLARITY_NEGATIVE] = "negative" +}; + static ssize_t counter_comp_u8_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -201,6 +206,8 @@ static ssize_t counter_comp_u32_show(struct device *dev, return sysfs_emit(buf, "%s\n", counter_count_direction_str[data]); case COUNTER_COMP_COUNT_MODE: return sysfs_emit(buf, "%s\n", counter_count_mode_str[data]); + case COUNTER_COMP_SIGNAL_POLARITY: + return sysfs_emit(buf, "%s\n", counter_signal_polarity_str[data]); default: return sysfs_emit(buf, "%u\n", (unsigned int)data); } @@ -252,6 +259,10 @@ static ssize_t counter_comp_u32_store(struct device *dev, err = counter_find_enum(&data, avail->enums, avail->num_items, buf, counter_count_mode_str); break; + case COUNTER_COMP_SIGNAL_POLARITY: + err = counter_find_enum(&data, avail->enums, avail->num_items, + buf, counter_signal_polarity_str); + break; default: err = kstrtou32(buf, 0, &data); break; @@ -469,6 +480,7 @@ static int counter_attr_create(struct device *const dev, case COUNTER_COMP_ENUM: case COUNTER_COMP_COUNT_DIRECTION: case COUNTER_COMP_COUNT_MODE: + case COUNTER_COMP_SIGNAL_POLARITY: if (comp->device_u32_read) { dev_attr->attr.mode |= 0444; dev_attr->show = counter_comp_u32_show; |