From 06a09124b5ec65f81df66c56695d9a9ae04a0114 Mon Sep 17 00:00:00 2001 From: Michael Hennerich Date: Tue, 9 Mar 2010 20:38:45 -0800 Subject: [PATCH] Input: ads7846 - add support for AD7843 parts The AD7873 is almost identical to the ADS7846; the only difference is related to the Power Management bits PD0 and PD1. This results in a slightly different PENIRQ enable behavior. For the AD7873, VREF should be turned off during differential measurements. So, add the AD7873/43 to the list of driver supported devices, and prevent VREF usage during differential/ratiometric conversion modes. Signed-off-by: Michael Hennerich Signed-off-by: Mike Frysinger Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/Kconfig | 9 +++++---- drivers/input/touchscreen/ads7846.c | 10 ++++++++++ include/linux/spi/ads7846.h | 2 +- 3 files changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 7208654..8a8fa4d 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -24,17 +24,18 @@ config TOUCHSCREEN_88PM860X module will be called 88pm860x-ts. config TOUCHSCREEN_ADS7846 - tristate "ADS7846/TSC2046 and ADS7843 based touchscreens" + tristate "ADS7846/TSC2046/AD7873 and AD(S)7843 based touchscreens" depends on SPI_MASTER depends on HWMON = n || HWMON help Say Y here if you have a touchscreen interface using the - ADS7846/TSC2046 or ADS7843 controller, and your board-specific - setup code includes that in its table of SPI devices. + ADS7846/TSC2046/AD7873 or ADS7843/AD7843 controller, + and your board-specific setup code includes that in its + table of SPI devices. If HWMON is selected, and the driver is told the reference voltage on your board, you will also get hwmon interfaces for the voltage - (and on ads7846/tsc2046, temperature) sensors of this chip. + (and on ads7846/tsc2046/ad7873, temperature) sensors of this chip. If unsure, say N (but it's safe to say "Y"). diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c index 8b05d8e..d187be0 100644 --- a/drivers/input/touchscreen/ads7846.c +++ b/drivers/input/touchscreen/ads7846.c @@ -36,6 +36,7 @@ * TSC2046 is just newer ads7846 silicon. * Support for ads7843 tested on Atmel at91sam926x-EK. * Support for ads7845 has only been stubbed in. + * Support for Analog Devices AD7873 and AD7843 tested. * * IRQ handling needs a workaround because of a shortcoming in handling * edge triggered IRQs on some platforms like the OMAP1/2. These @@ -984,6 +985,15 @@ static int __devinit ads7846_probe(struct spi_device *spi) vref = pdata->keep_vref_on; + if (ts->model == 7873) { + /* The AD7873 is almost identical to the ADS7846 + * keep VREF off during differential/ratiometric + * conversion modes + */ + ts->model = 7846; + vref = 0; + } + /* set up the transfers to read touchscreen state; this assumes we * use formula #2 for pressure, not #3. */ diff --git a/include/linux/spi/ads7846.h b/include/linux/spi/ads7846.h index 51948eb..5710c15 100644 --- a/include/linux/spi/ads7846.h +++ b/include/linux/spi/ads7846.h @@ -12,7 +12,7 @@ enum ads7846_filter { }; struct ads7846_platform_data { - u16 model; /* 7843, 7845, 7846. */ + u16 model; /* 7843, 7845, 7846, 7873. */ u16 vref_delay_usecs; /* 0 for external vref; etc */ u16 vref_mv; /* external vref value, milliVolts */ bool keep_vref_on; /* set to keep vref on for differential -- 2.7.4