From 50d3ff39d4557cda87194c7b11ac76429bd1bf2a Mon Sep 17 00:00:00 2001 From: patacongo Date: Mon, 3 Oct 2011 16:47:23 +0000 Subject: The ADS7843E driver skeleton at least compiles now git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4014 42af7a65-404d-4744-a932-0658087f49c3 --- nuttx/drivers/input/ads7843e.c | 145 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 143 insertions(+), 2 deletions(-) (limited to 'nuttx/drivers') diff --git a/nuttx/drivers/input/ads7843e.c b/nuttx/drivers/input/ads7843e.c index d03a64b44..d92073b72 100644 --- a/nuttx/drivers/input/ads7843e.c +++ b/nuttx/drivers/input/ads7843e.c @@ -2,7 +2,8 @@ * drivers/input/ads7843e.c * * Copyright (C) 2011 Gregory Nutt. All rights reserved. - * Author: Gregory Nutt + * Authors: Gregory Nutt + * Diego Sanchez * * References: * "Touch Screen Controller, ADS7843," Burr-Brown Products from Texas @@ -144,6 +145,18 @@ struct ads7843e_dev_s /**************************************************************************** * Private Function Prototypes ****************************************************************************/ +/* Low-level SPI helpers */ + +static inline void ads7843e_configspi(FAR struct spi_dev_s *spi); +#ifdef CONFIG_SPI_OWNBUS +static inline void ads7843e_select(FAR struct spi_dev_s *spi); +static inline void ads7843e_deselect(FAR struct spi_dev_s *spi); +#else +static void ads7843e_select(FAR struct spi_dev_s *spi); +static void ads7843e_deselect(FAR struct spi_dev_s *spi); +#endif + +/* Interrupts and data sampling */ static void ads7843e_notify(FAR struct ads7843e_dev_s *priv); static int ads7843e_sample(FAR struct ads7843e_dev_s *priv, @@ -200,6 +213,133 @@ static struct ads7843e_dev_s *g_ads7843elist; * Private Functions ****************************************************************************/ +/**************************************************************************** + * Function: ads7843e_configspi + * + * Description: + * Configure the SPI for use with the ADS7843E. This funcution should be + * called once during touchscreen initialization to configure the SPI + * bus. Note that if CONFIG_SPI_OWNBUS is not defined, then this function + * does nothing. + * + * Parameters: + * spi - Reference to the SPI driver structure + * + * Returned Value: + * None + * + * Assumptions: + * + ****************************************************************************/ + +static inline void ads7843e_configspi(FAR struct spi_dev_s *spi) +{ +#ifdef CONFIG_ADS7843E_FREQUENCY + idbg("Mode: %d Bits: 8 Frequency: %d\n", + CONFIG_ADS7843E_SPIMODE, CONFIG_ADS7843E_FREQUENCY); +#else + idbg("Mode: %d Bits: 8\n", CONFIG_ADS7843E_SPIMODE); +#endif + + /* Configure SPI for the P14201. But only if we own the SPI bus. Otherwise, don't + * bother because it might change. + */ + +#ifdef CONFIG_SPI_OWNBUS + SPI_SETMODE(spi, CONFIG_ADS7843E_SPIMODE); + SPI_SETBITS(spi, 8); +#ifdef CONFIG_ADS7843E_FREQUENCY + SPI_SETFREQUENCY(spi, CONFIG_ADS7843E_FREQUENCY) +#endif +#endif +} + +/**************************************************************************** + * Function: ads7843e_select + * + * Description: + * Select the SPI, locking and re-configuring if necessary. This function + * must be called before initiating any sequence of SPI operations. If we + * are sharing the SPI bus with other devices (CONFIG_SPI_OWNBUS undefined) + * then we need to lock and configure the SPI bus for each transfer. + * + * Parameters: + * spi - Reference to the SPI driver structure + * + * Returned Value: + * None + * + * Assumptions: + * + ****************************************************************************/ + +#ifdef CONFIG_SPI_OWNBUS +static inline void ads7843e_select(FAR struct spi_dev_s *spi) +{ + /* We own the SPI bus, so just select the chip */ + + SPI_SELECT(spi, SPIDEV_DISPLAY, true); +} +#else +static void ads7843e_select(FAR struct spi_dev_s *spi) +{ + /* Select P14201 chip (locking the SPI bus in case there are multiple + * devices competing for the SPI bus + */ + + SPI_LOCK(spi, true); + SPI_SELECT(spi, SPIDEV_DISPLAY, true); + + /* Now make sure that the SPI bus is configured for the P14201 (it + * might have gotten configured for a different device while unlocked) + */ + + SPI_SETMODE(spi, CONFIG_ADS7843E_SPIMODE); + SPI_SETBITS(spi, 8); +#ifdef CONFIG_ADS7843E_FREQUENCY + SPI_SETFREQUENCY(spi, CONFIG_ADS7843E_FREQUENCY); +#endif +} +#endif + + +/**************************************************************************** + * Function: ads7843e_deselect + * + * Description: + * De-select the SPI, unlocking as necessary. This function must be + * after completing asequence of SPI operations. If we are sharing the SPI + * bus with other devices (CONFIG_SPI_OWNBUS undefined) then we need to + * un-lock the SPI bus for each transfer, possibly losing the current + * configuration. + * + * Parameters: + * spi - Reference to the SPI driver structure + * + * Returned Value: + * None + * + * Assumptions: + * + ****************************************************************************/ + +#ifdef CONFIG_SPI_OWNBUS +static inline void ads7843e_deselect(FAR struct spi_dev_s *spi) +{ + /* We own the SPI bus, so just de-select the chip */ + + SPI_SELECT(spi, SPIDEV_DISPLAY, false); +} +#else +static void ads7843e_deselect(FAR struct spi_dev_s *spi) +{ + /* De-select P14201 chip and relinquish the SPI bus. */ + + SPI_SELECT(spi, SPIDEV_DISPLAY, false); + SPI_LOCK(spi, false); +} +#endif + /**************************************************************************** * Name: ads7843e_notify ****************************************************************************/ @@ -944,7 +1084,6 @@ int ads7843e_register(FAR struct spi_dev_s *dev, /* Debug-only sanity checks */ DEBUGASSERT(dev != NULL && config != NULL && minor >= 0 && minor < 100); - DEBUGASSERT((config->address & 0xfc) == 0x48); DEBUGASSERT(config->attach != NULL && config->enable != NULL && config->clear != NULL && config->pendown != NULL); @@ -988,6 +1127,8 @@ int ads7843e_register(FAR struct spi_dev_s *dev, } /* Initialize the touchscreen device */ + + ads7843e_configspi(dev); #warning "Missing logic" /* Register the device as an input device */ -- cgit v1.2.3