From: Marek Vasut <marex@denx.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 14/24] mxc_i2c: add retries
Date: Fri, 22 Jun 2012 19:06:03 +0200 [thread overview]
Message-ID: <201206221906.03647.marex@denx.de> (raw)
In-Reply-To: <1340338339-11626-14-git-send-email-troy.kisky@boundarydevices.com>
Dear Troy Kisky,
> Retry unexpected hardware errors. This
> will not retry a received NAK.
>
> Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Why do you need this? Are you getting transmission errors? I think it's because
you broke something in the driver, I was getting errors, but managed to hack it
together in such a manner, that they didn't happen anymore.
> ---
> drivers/i2c/mxc_i2c.c | 36 +++++++++++++++++++++++++++---------
> 1 file changed, 27 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
> index df033ea..802f70f 100644
> --- a/drivers/i2c/mxc_i2c.c
> +++ b/drivers/i2c/mxc_i2c.c
> @@ -213,7 +213,7 @@ void i2c_imx_stop(void)
> * Send start signal, chip address and
> * write register address
> */
> -static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
> +static int i2c_init_transfer_(struct mxc_i2c_regs *i2c_regs,
> uchar chip, uint addr, int alen)
> {
> unsigned int temp;
> @@ -230,7 +230,7 @@ static int i2c_init_transfer(struct mxc_i2c_regs
> *i2c_regs, writeb(0, &i2c_regs->i2sr);
> ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
> if (ret < 0)
> - goto exit;
> + return ret;
>
> /* Start I2C transaction */
> temp = readb(&i2c_regs->i2cr);
> @@ -239,7 +239,7 @@ static int i2c_init_transfer(struct mxc_i2c_regs
> *i2c_regs,
>
> ret = wait_for_sr_state(i2c_regs, ST_BUS_BUSY);
> if (ret < 0)
> - goto exit;
> + return ret;
>
> temp |= I2CR_MTX | I2CR_TX_NO_AK;
> writeb(temp, &i2c_regs->i2cr);
> @@ -247,18 +247,36 @@ static int i2c_init_transfer(struct mxc_i2c_regs
> *i2c_regs, /* write slave address */
> ret = tx_byte(i2c_regs, chip << 1);
> if (ret < 0)
> - goto exit;
> + return ret;
>
> while (alen--) {
> ret = tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
> if (ret < 0)
> - goto exit;
> + return ret;
> }
> return 0;
> -exit:
> - i2c_imx_stop();
> - /* Disable I2C controller */
> - writeb(0, &i2c_regs->i2cr);
> +}
> +
> +static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
> + uchar chip, uint addr, int alen)
> +{
> + int retry;
> + int ret;
> + for (retry = 0; retry < 3; retry++) {
> + ret = i2c_init_transfer_(i2c_regs, chip, addr, alen);
> + if (ret >= 0)
> + return ret;
> + i2c_imx_stop(i2c_regs);
> + if (ret == -ENODEV)
> + return ret;
> +
> + printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
> + retry);
> + if (ret != -ERESTART)
> + writeb(0, &i2c_regs->i2cr); /* Disable controller */
> + udelay(100);
> + }
> + printf("%s: give up i2c_regs=%p\n", __func__, i2c_regs);
> return ret;
> }
Best regards,
Marek Vasut
next prev parent reply other threads:[~2012-06-22 17:06 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-22 4:11 [U-Boot] [PATCH 01/24] mxc_i2c: fix i2c_imx_stop Troy Kisky
2012-06-22 4:11 ` [U-Boot] [PATCH 02/24] mxc_i2c: remove ifdef of CONFIG_HARD_I2C Troy Kisky
2012-06-22 16:55 ` Marek Vasut
2012-06-22 4:11 ` [U-Boot] [PATCH 03/24] mxc_i2c: create tx_byte function Troy Kisky
2012-06-22 16:58 ` Marek Vasut
2012-06-22 23:05 ` Troy Kisky
2012-06-23 1:51 ` Marek Vasut
2012-06-22 4:11 ` [U-Boot] [PATCH 04/24] mxc_i2c: clear i2sr before waiting for bit Troy Kisky
2012-06-22 16:59 ` Marek Vasut
2012-06-24 0:18 ` Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 05/24] mxc_i2c: create i2c_init_transfer Troy Kisky
2012-06-22 16:59 ` Marek Vasut
2012-06-24 8:06 ` Stefano Babic
2012-06-22 4:12 ` [U-Boot] [PATCH 06/24] mxc_i2c.c: code i2c_probe as a 0 length i2c_write Troy Kisky
2012-06-22 17:00 ` Marek Vasut
2012-06-24 8:03 ` Stefano Babic
2012-06-22 4:12 ` [U-Boot] [PATCH 07/24] mxc_i2c: combine i2c_imx_bus_busy and i2c_imx_trx_complete into wait_for_sr_state Troy Kisky
2012-06-22 17:01 ` Marek Vasut
2012-06-22 17:34 ` Troy Kisky
2012-06-22 18:01 ` Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 08/24] mxc_i2c: remove redundant read Troy Kisky
2012-06-22 17:02 ` Marek Vasut
2012-06-22 4:12 ` [U-Boot] [PATCH 09/24] mxc_i2c: place imx_start code inline Troy Kisky
2012-06-22 17:02 ` Marek Vasut
2012-06-22 4:12 ` [U-Boot] [PATCH 10/24] mxc_i2c: place i2c_reset " Troy Kisky
2012-06-22 17:03 ` Marek Vasut
2012-06-22 4:12 ` [U-Boot] [PATCH 11/24] mxc_i2c: don't disable controller after every transaction Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 12/24] mxc_i2c: change slave addr if conflicts with destination Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 13/24] mxc_i2c: check for arbitration lost Troy Kisky
2012-06-22 17:04 ` Marek Vasut
2012-06-22 4:12 ` [U-Boot] [PATCH 14/24] mxc_i2c: add retries Troy Kisky
2012-06-22 17:06 ` Marek Vasut [this message]
2012-06-22 17:40 ` Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 15/24] mxc_i2c: add i2c_regs argument to i2c_imx_stop Troy Kisky
2012-06-22 17:06 ` Marek Vasut
2012-06-22 4:12 ` [U-Boot] [PATCH 16/24] mxc_i2c: prep work for multiple busses support Troy Kisky
2012-06-22 17:08 ` Marek Vasut
2012-06-24 8:47 ` Heiko Schocher
2012-06-24 20:08 ` Marek Vasut
2012-06-24 22:09 ` Wolfgang Denk
2012-06-22 4:12 ` [U-Boot] [PATCH 17/24] mxc_i2c: add bus recovery support Troy Kisky
2012-06-24 8:51 ` Heiko Schocher
2012-06-26 3:42 ` Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 18/24] mxc_i2c.c: finish adding CONFIG_I2C_MULTI_BUS support Troy Kisky
2012-06-22 17:09 ` Marek Vasut
2012-06-22 19:41 ` Troy Kisky
2012-06-25 3:34 ` Tabi Timur-B04825
2012-06-22 4:12 ` [U-Boot] [PATCH 19/24] iomux-v3: remove include of mx6x_pins.h Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 20/24] i.mx: iomux-v3.h: move to imx-common include directory Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 21/24] i.mx: iomux-v3.c: move to imx-common directory Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 22/24] i.mx53: add definition for I2C3_BASE_ADDR Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 23/24] imx-common: add i2c.c for bus recovery support Troy Kisky
2012-06-22 4:12 ` [U-Boot] [PATCH 24/24] mx6qsabrelite: add i2c multi-bus support Troy Kisky
2012-06-22 16:55 ` [U-Boot] [PATCH 01/24] mxc_i2c: fix i2c_imx_stop Marek Vasut
2012-06-24 7:49 ` Stefano Babic
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