From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: =?UTF-8?q?=5BPATCH=202/4=5D=20MXS=3A=20Set=20I2C=20timing=20registers=20for=20mxs-i2c?= Date: Tue, 1 May 2012 04:00:19 +0200 Message-ID: <1335837621-14816-3-git-send-email-marex@denx.de> References: <1335837621-14816-1-git-send-email-marex@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1335837621-14816-1-git-send-email-marex-ynQEQJNshbs@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Cc: Marek Vasut , Detlev Zundel , Dong Aisheng , Fabio Estevam , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Sascha Hauer , Shawn Guo , Stefano Babic , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Wolfgang Denk , Wolfram Sang List-Id: linux-i2c@vger.kernel.org This patch configures the I2C bus timing registers according to information passed via platform data. Currently, 100kHz and 400kHz modes are supported. Signed-off-by: Marek Vasut Cc: Detlev Zundel CC: Dong Aisheng CC: Fabio Estevam Cc: Linux ARM kernel Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org CC: Sascha Hauer CC: Shawn Guo Cc: Stefano Babic CC: Uwe Kleine-K=C3=B6nig Cc: Wolfgang Denk Cc: Wolfram Sang --- drivers/i2c/busses/i2c-mxs.c | 42 ++++++++++++++++++++++++++++++++++= ++++++++ 1 file changed, 42 insertions(+) diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.= c index 3d471d5..717b7f9 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -43,6 +44,10 @@ #define MXS_I2C_CTRL0_DIRECTION 0x00010000 #define MXS_I2C_CTRL0_XFER_COUNT(v) ((v) & 0x0000FFFF) =20 +#define MXS_I2C_TIMING0 (0x10) +#define MXS_I2C_TIMING1 (0x20) +#define MXS_I2C_TIMING2 (0x30) + #define MXS_I2C_CTRL1 (0x40) #define MXS_I2C_CTRL1_SET (0x44) #define MXS_I2C_CTRL1_CLR (0x48) @@ -94,6 +99,25 @@ #define MXS_CMD_I2C_READ (MXS_I2C_CTRL0_SEND_NAK_ON_LAST | \ MXS_I2C_CTRL0_MASTER_MODE) =20 + +struct mxs_i2c_speed_config { + uint32_t timing0; + uint32_t timing1; + uint32_t timing2; +}; + +const struct mxs_i2c_speed_config mxs_i2c_95kHz_config =3D { + .timing0 =3D 0x00780030, + .timing1 =3D 0x00800030, + .timing2 =3D 0x0015000d, +}; + +const struct mxs_i2c_speed_config mxs_i2c_400kHz_config =3D { + .timing0 =3D 0x000f0007, + .timing1 =3D 0x001f000f, + .timing2 =3D 0x0015000d, +}; + /** * struct mxs_i2c_dev - per device, private MXS-I2C data * @@ -109,6 +133,7 @@ struct mxs_i2c_dev { struct completion cmd_complete; u32 cmd_err; struct i2c_adapter adapter; + const struct mxs_i2c_speed_config *speed; }; =20 /* @@ -118,6 +143,11 @@ struct mxs_i2c_dev { static void mxs_i2c_reset(struct mxs_i2c_dev *i2c) { mxs_reset_block(i2c->regs); + + writel(i2c->speed->timing0, i2c->regs + MXS_I2C_TIMING0); + writel(i2c->speed->timing1, i2c->regs + MXS_I2C_TIMING1); + writel(i2c->speed->timing2, i2c->regs + MXS_I2C_TIMING2); + writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET); writel(MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE, i2c->regs + MXS_I2C_QUEUECTRL_SET); @@ -321,12 +351,16 @@ static const struct i2c_algorithm mxs_i2c_algo =3D= { static int __devinit mxs_i2c_probe(struct platform_device *pdev) { struct device *dev =3D &pdev->dev; + struct mxs_i2c_platform_data *pdata =3D pdev->dev.platform_data; struct mxs_i2c_dev *i2c; struct i2c_adapter *adap; struct resource *res; resource_size_t res_size; int err, irq; =20 + if (!pdata) + return -ENODEV; + i2c =3D devm_kzalloc(dev, sizeof(struct mxs_i2c_dev), GFP_KERNEL); if (!i2c) return -ENOMEM; @@ -352,6 +386,14 @@ static int __devinit mxs_i2c_probe(struct platform= _device *pdev) return err; =20 i2c->dev =3D dev; + + /* Configure the bus speed. */ + i2c->speed =3D &mxs_i2c_95kHz_config; + if (pdata->speed_khz =3D=3D 400) + i2c->speed =3D &mxs_i2c_400kHz_config; + else if (pdata->speed_khz !=3D 100) + dev_err(dev, "Invalid I2C speed selected, using 100kHz\n"); + platform_set_drvdata(pdev, i2c); =20 /* Do reset to enforce correct startup after pinmuxing */ --=20 1.7.10