From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751542AbbKNKGU (ORCPT ); Sat, 14 Nov 2015 05:06:20 -0500 Received: from mail-lb0-f171.google.com ([209.85.217.171]:32796 "EHLO mail-lb0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751051AbbKNKGQ (ORCPT ); Sat, 14 Nov 2015 05:06:16 -0500 Subject: Re: [PATCH v3 5/7] spi: imx: Add support for loopback for ECSPI controllers To: broonie@kernel.org, b38343@freescale.com References: <1446388901-6073-1-git-send-email-anton.bondarenko.sama@gmail.com> <1446388901-6073-6-git-send-email-anton.bondarenko.sama@gmail.com> Cc: linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, vladimir_zapolskiy@mentor.com, jiada_wang@mentor.com, s.hauer@pengutronix.de From: Anton Bondarenko Message-ID: <56470795.8090602@gmail.com> Date: Sat, 14 Nov 2015 11:06:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <1446388901-6073-6-git-send-email-anton.bondarenko.sama@gmail.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01.11.2015 15:41, Anton Bondarenko wrote: > From: Anton Bondarenko > > Support for ECSPI loopback for IMX51,IMX53 and IMX6Q using TEST register. > > Signed-off-by: Mohsin Kazmi > Signed-off-by: Anton Bondarenko > --- > drivers/spi/spi-imx.c | 19 ++++++++++++++++--- > 1 file changed, 16 insertions(+), 3 deletions(-) > > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c > index 48fdfa1..dc492e2 100644 > --- a/drivers/spi/spi-imx.c > +++ b/drivers/spi/spi-imx.c > @@ -270,6 +270,9 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, > #define MX51_ECSPI_STAT 0x18 > #define MX51_ECSPI_STAT_RR (1 << 3) > > +#define MX51_ECSPI_TEST 0x20 > +#define MX51_ECSPI_LOOP BIT(31) > + > /* MX51 eCSPI */ > static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi, > unsigned int *fres) > @@ -343,6 +346,7 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, > u32 ctrl = MX51_ECSPI_CTRL_ENABLE, dma = 0; > u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG); > u32 delay; > + u32 lpb = 0; > > /* > * The hardware seems to have a race condition when changing modes. The > @@ -385,6 +389,12 @@ static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, > writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); > writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG); > > + if (config->mode & SPI_LOOP) > + lpb |= MX51_ECSPI_LOOP; > + > + if ((readl(spi_imx->base + MX51_ECSPI_TEST) & MX51_ECSPI_LOOP) != lpb) > + writel(lpb, spi_imx->base + MX51_ECSPI_TEST); > + > /* > * Wait until the changes in the configuration register CONFIGREG > * propagate into the hardware. It takes exactly one tick of the > @@ -1262,6 +1272,9 @@ static int spi_imx_probe(struct platform_device *pdev) > spi_imx = spi_master_get_devdata(master); > spi_imx->bitbang.master = master; > > + spi_imx->devtype_data = of_id ? of_id->data : > + (struct spi_imx_devtype_data *)pdev->id_entry->driver_data; > + > for (i = 0; i < master->num_chipselect; i++) { > int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); > if (!gpio_is_valid(cs_gpio) && mxc_platform_info) > @@ -1288,10 +1301,10 @@ static int spi_imx_probe(struct platform_device *pdev) > spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message; > spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; > > - init_completion(&spi_imx->xfer_done); > + if (is_imx51_ecspi(spi_imx)) > + spi_imx->bitbang.master->mode_bits |= SPI_LOOP; > > - spi_imx->devtype_data = of_id ? of_id->data : > - (struct spi_imx_devtype_data *) pdev->id_entry->driver_data; > + init_completion(&spi_imx->xfer_done); > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > spi_imx->base = devm_ioremap_resource(&pdev->dev, res); > Does anyone has other comments regarding this commit? Regards, Anton