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81f2a5b4a0
Now LP55xx provides automatic clock detection API, lp55xx_is_extclk_used(). The clock configuration can be done by the driver itself. (a) Concept The default value is set by each driver with clock selection. The internal clock selection bit is updated in case that the external clock is not detected or clock rate is not 32KHz. (b) Change on LP55xx platform data The clock configuration is done automatically, so no need to define 'update_config' in the platform side. Correlated information are removed in the documentations and header. (c) Definitions moved from header to driver files CONFIG register values are moved each driver, LP5521 and LP5562. Not necessary definitions are removed also. Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Bryan Wu <cooloney@gmail.com>
84 lines
2.4 KiB
Plaintext
84 lines
2.4 KiB
Plaintext
Kernel driver for lp5521
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========================
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* National Semiconductor LP5521 led driver chip
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* Datasheet: http://www.national.com/pf/LP/LP5521.html
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Authors: Mathias Nyman, Yuri Zaporozhets, Samu Onkalo
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Contact: Samu Onkalo (samu.p.onkalo-at-nokia.com)
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Description
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-----------
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LP5521 can drive up to 3 channels. Leds can be controlled directly via
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the led class control interface. Channels have generic names:
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lp5521:channelx, where x is 0 .. 2
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All three channels can be also controlled using the engine micro programs.
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More details of the instructions can be found from the public data sheet.
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LP5521 has the internal program memory for running various LED patterns.
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For the details, please refer to 'firmware' section in leds-lp55xx.txt
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sysfs contains a selftest entry.
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The test communicates with the chip and checks that
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the clock mode is automatically set to the requested one.
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Each channel has its own led current settings.
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/sys/class/leds/lp5521:channel0/led_current - RW
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/sys/class/leds/lp5521:channel0/max_current - RO
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Format: 10x mA i.e 10 means 1.0 mA
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example platform data:
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Note: chan_nr can have values between 0 and 2.
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The name of each channel can be configurable.
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If the name field is not defined, the default name will be set to 'xxxx:channelN'
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(XXXX : pdata->label or i2c client name, N : channel number)
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static struct lp55xx_led_config lp5521_led_config[] = {
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{
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.name = "red",
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.chan_nr = 0,
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.led_current = 50,
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.max_current = 130,
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}, {
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.name = "green",
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.chan_nr = 1,
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.led_current = 0,
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.max_current = 130,
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}, {
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.name = "blue",
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.chan_nr = 2,
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.led_current = 0,
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.max_current = 130,
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}
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};
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static int lp5521_setup(void)
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{
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/* setup HW resources */
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}
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static void lp5521_release(void)
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{
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/* Release HW resources */
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}
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static void lp5521_enable(bool state)
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{
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/* Control of chip enable signal */
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}
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static struct lp55xx_platform_data lp5521_platform_data = {
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.led_config = lp5521_led_config,
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.num_channels = ARRAY_SIZE(lp5521_led_config),
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.clock_mode = LP55XX_CLOCK_EXT,
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.setup_resources = lp5521_setup,
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.release_resources = lp5521_release,
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.enable = lp5521_enable,
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};
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If the current is set to 0 in the platform data, that channel is
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disabled and it is not visible in the sysfs.
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