Patchwork spi_mpc8xxx.c: chip select polarity problem

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Submitter Torsten Fleischer
Date Nov. 21, 2009, 4:08 p.m.
Message ID <200911211708.47253.to-fleischer@t-online.de>
Download mbox | patch
Permalink /patch/38985/
State Changes Requested
Delegated to: Grant Likely
Headers show

Comments

Torsten Fleischer - Nov. 21, 2009, 4:08 p.m.
On Sat, Nov 21, 2009 at 09:45:50 Grant Likely wrote:
[...]
> Hey Torsten,  do you have an updated version of this change to address
> the comments?  I'm collecting the last few things for some linux-next
> exposure now.

Hey Grant,

here is the updated version of the patch containing the recommended
changes.

Best Regards
Torsten


Signed-off-by: Torsten Fleischer <to-fleischer@t-online.de>
---
Grant Likely - Nov. 25, 2009, 12:33 a.m.
Thanks.  However, there needs to be a proper description of what this
patch does to go in the commit header.  Can you please write one?

Thanks,
g.

On Sat, Nov 21, 2009 at 9:08 AM, Torsten Fleischer
<to-fleischer@t-online.de> wrote:
> On Sat, Nov 21, 2009 at 09:45:50 Grant Likely wrote:
> [...]
>> Hey Torsten,  do you have an updated version of this change to address
>> the comments?  I'm collecting the last few things for some linux-next
>> exposure now.
>
> Hey Grant,
>
> here is the updated version of the patch containing the recommended
> changes.
>
> Best Regards
> Torsten
>
>
> Signed-off-by: Torsten Fleischer <to-fleischer@t-online.de>
> ---
>
> diff -u -r -N linux-2.6.31.6_orig//drivers/spi/spi_mpc8xxx.c linux-2.6.31.6/drivers/spi/spi_mpc8xxx.c
> --- linux-2.6.31.6_orig//drivers/spi/spi_mpc8xxx.c      2009-11-10 01:32:31.000000000 +0100
> +++ linux-2.6.31.6/drivers/spi/spi_mpc8xxx.c    2009-11-19 08:15:33.000000000 +0100
> @@ -114,6 +114,7 @@
>        u32 rx_shift;           /* RX data reg shift when in qe mode */
>        u32 tx_shift;           /* TX data reg shift when in qe mode */
>        u32 hw_mode;            /* Holds HW mode register settings */
> +       int initialized;
>  };
>
>  static inline void mpc8xxx_spi_write_reg(__be32 __iomem *reg, u32 val)
> @@ -503,15 +504,52 @@
>
>        return ret;
>  }
> +
> +
> +struct mpc8xxx_spi_probe_info {
> +       struct fsl_spi_platform_data pdata;
> +       int *gpios;
> +       bool *alow_flags;
> +};
> +
> +static struct mpc8xxx_spi_probe_info *
> +to_of_pinfo(struct fsl_spi_platform_data *pdata)
> +{
> +       return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
> +}
> +
> +static int mpc8xxx_spi_cs_init(struct spi_device *spi)
> +{
> +       struct device *dev = spi->dev.parent;
> +       struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
> +       u16 cs = spi->chip_select;
> +       int gpio = pinfo->gpios[cs];
> +       bool on = pinfo->alow_flags[cs] ^ !(spi->mode & SPI_CS_HIGH);
> +
> +       return gpio_direction_output(gpio, on);
> +}
> +
>  static int mpc8xxx_spi_transfer(struct spi_device *spi,
>                                struct spi_message *m)
>  {
>        struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
> +       struct spi_mpc8xxx_cs *cs = spi->controller_state;
>        unsigned long flags;
>
>        m->actual_length = 0;
>        m->status = -EINPROGRESS;
>
> +       if (cs && !cs->initialized) {
> +               int ret;
> +
> +               ret = mpc8xxx_spi_cs_init(spi);
> +               if (ret) {
> +                       dev_dbg(&spi->dev, "cs_init failed: %d\n", ret);
> +                       return ret;
> +               }
> +               cs->initialized = 1;
> +       }
> +
>        spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
>        list_add_tail(&m->queue, &mpc8xxx_spi->queue);
>        queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
> @@ -648,18 +686,6 @@
>        return 0;
>  }
>
> -struct mpc8xxx_spi_probe_info {
> -       struct fsl_spi_platform_data pdata;
> -       int *gpios;
> -       bool *alow_flags;
> -};
> -
> -static struct mpc8xxx_spi_probe_info *
> -to_of_pinfo(struct fsl_spi_platform_data *pdata)
> -{
> -       return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
> -}
> -
>  static void mpc8xxx_spi_cs_control(struct spi_device *spi, bool on)
>  {
>        struct device *dev = spi->dev.parent;
> @@ -720,14 +746,6 @@
>
>                pinfo->gpios[i] = gpio;
>                pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
> -
> -               ret = gpio_direction_output(pinfo->gpios[i],
> -                                           pinfo->alow_flags[i]);
> -               if (ret) {
> -                       dev_err(dev, "can't set output direction for gpio "
> -                               "#%d: %d\n", i, ret);
> -                       goto err_loop;
> -               }
>        }
>
>        pdata->max_chipselect = ngpios;
>

Patch

diff -u -r -N linux-2.6.31.6_orig//drivers/spi/spi_mpc8xxx.c linux-2.6.31.6/drivers/spi/spi_mpc8xxx.c
--- linux-2.6.31.6_orig//drivers/spi/spi_mpc8xxx.c	2009-11-10 01:32:31.000000000 +0100
+++ linux-2.6.31.6/drivers/spi/spi_mpc8xxx.c	2009-11-19 08:15:33.000000000 +0100
@@ -114,6 +114,7 @@ 
 	u32 rx_shift;		/* RX data reg shift when in qe mode */
 	u32 tx_shift;		/* TX data reg shift when in qe mode */
 	u32 hw_mode;		/* Holds HW mode register settings */
+	int initialized;
 };
 
 static inline void mpc8xxx_spi_write_reg(__be32 __iomem *reg, u32 val)
@@ -503,15 +504,52 @@ 
 
 	return ret;
 }
+
+
+struct mpc8xxx_spi_probe_info {
+	struct fsl_spi_platform_data pdata;
+	int *gpios;
+	bool *alow_flags;
+};
+
+static struct mpc8xxx_spi_probe_info *
+to_of_pinfo(struct fsl_spi_platform_data *pdata)
+{
+	return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
+}
+
+static int mpc8xxx_spi_cs_init(struct spi_device *spi)
+{
+	struct device *dev = spi->dev.parent;
+	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
+	u16 cs = spi->chip_select;
+	int gpio = pinfo->gpios[cs];
+	bool on = pinfo->alow_flags[cs] ^ !(spi->mode & SPI_CS_HIGH);
+
+	return gpio_direction_output(gpio, on);
+}
+
 static int mpc8xxx_spi_transfer(struct spi_device *spi,
 				struct spi_message *m)
 {
 	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	struct spi_mpc8xxx_cs *cs = spi->controller_state;
 	unsigned long flags;
 
 	m->actual_length = 0;
 	m->status = -EINPROGRESS;
 
+	if (cs && !cs->initialized) {
+		int ret;
+
+		ret = mpc8xxx_spi_cs_init(spi);
+		if (ret) {
+			dev_dbg(&spi->dev, "cs_init failed: %d\n", ret);
+			return ret;
+		}
+		cs->initialized = 1;
+	}
+
 	spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
 	list_add_tail(&m->queue, &mpc8xxx_spi->queue);
 	queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
@@ -648,18 +686,6 @@ 
 	return 0;
 }
 
-struct mpc8xxx_spi_probe_info {
-	struct fsl_spi_platform_data pdata;
-	int *gpios;
-	bool *alow_flags;
-};
-
-static struct mpc8xxx_spi_probe_info *
-to_of_pinfo(struct fsl_spi_platform_data *pdata)
-{
-	return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
-}
-
 static void mpc8xxx_spi_cs_control(struct spi_device *spi, bool on)
 {
 	struct device *dev = spi->dev.parent;
@@ -720,14 +746,6 @@ 
 
 		pinfo->gpios[i] = gpio;
 		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
-
-		ret = gpio_direction_output(pinfo->gpios[i],
-					    pinfo->alow_flags[i]);
-		if (ret) {
-			dev_err(dev, "can't set output direction for gpio "
-				"#%d: %d\n", i, ret);
-			goto err_loop;
-		}
 	}
 
 	pdata->max_chipselect = ngpios;