[PATCH 2/2] spi: davinci: add support to configure gpio cs through dt
From: broonie@kernel.org (Mark Brown)
Date: 2014-07-31 19:35:15
Also in:
linux-devicetree, linux-spi
On Thu, Jul 31, 2014 at 08:33:15PM +0300, Grygorii Strashko wrote:
+ if (np && master->cs_gpios != NULL && spi->cs_gpio >= 0) {
+ /* SPI core parse and update master->cs_gpio */
gpio_chipsel = true;
+ gpio = spi->cs_gpio;
+ } else if (pdata->chip_sel &&
+ chip_sel < pdata->num_chipselect &&
+ pdata->chip_sel[chip_sel] != SPI_INTERN_CS) {
+ /* platform data defines chip_sel */
+ gpio_chipsel = true;
+ gpio = pdata->chip_sel[chip_sel];
+ }This would all be a lot simpler and more direct if you were to arrange to use cs_gpio in the struct spi_device, and move you closer to converting to use more of the core functionality.
+ if (np && (master->cs_gpios != NULL) && (spi->cs_gpio >= 0)) {
+ retval =
+ gpio_request(spi->cs_gpio, dev_name(&spi->dev));
+ if (retval) {
+ dev_err(&spi->dev,
+ "GPIO %d request failed\n",
+ spi->cs_gpio);
+ return -ENODEV;
+ }
+ gpio_direction_output(spi->cs_gpio,
+ !(spi->mode & SPI_CS_HIGH));
+ internal_cs = false;It's much better to use gpio_request_one() rather than using gpio_request(), it's one function apart from anything else. The above is also discarding the return code of gpio_request() meaning it's broken for deferred probe. The error code should also appear in the error message. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20140731/9580c14e/attachment.sig>