[v4 PATCH 05/12] spi/atmel_spi: update the dt support
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Tue Feb 5 15:04:56 EST 2013
On 15:34 Mon 14 Jan , Wenyou Yang wrote:
> To meet the different spi IP version of atmel SoC,
> add the more compatible with different config and devtype.
>
> The "has_dma_support" is used to select the dma engine transfer mode.
>
> The "has_wdrbt" indicate if there is the "WDRBT" bit in the Mode Register,
> WDRBT (Wait Data Read Before Transfer),if WDRBT is set,
> a transfer can start only if the Receive Data Register is empty,i.e. does not
> contain any unread data, to prevent overrun error in reception
>
> Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
> ---
> drivers/spi/spi-atmel.c | 134 ++++++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 115 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
> index 8f6f0a0..43c1f63 100644
> --- a/drivers/spi/spi-atmel.c
> +++ b/drivers/spi/spi-atmel.c
> @@ -71,6 +71,8 @@
> #define SPI_FDIV_SIZE 1
> #define SPI_MODFDIS_OFFSET 4
> #define SPI_MODFDIS_SIZE 1
> +#define SPI_WDRBT_OFFSET 5
> +#define SPI_WDRBT_SIZE 1
> #define SPI_LLB_OFFSET 7
> #define SPI_LLB_SIZE 1
> #define SPI_PCS_OFFSET 16
> @@ -186,6 +188,12 @@
> * DMA transfers; transfer queue progress is driven by IRQs. The clock
> * framework provides the base clock, subdivided for each spi_device.
> */
> +struct atmel_spi_pdata {
> + u8 version;
> + bool has_dma_support;
> + bool has_wdrbt;
> +};
> +
> struct atmel_spi {
> spinlock_t lock;
> unsigned long flags;
> @@ -204,6 +212,7 @@ struct atmel_spi {
> struct spi_transfer *next_transfer;
> unsigned long next_remaining_bytes;
> int done_status;
> + struct atmel_spi_pdata *pdata;
>
> void *buffer;
> dma_addr_t buffer_dma;
> @@ -218,6 +227,69 @@ struct atmel_spi_device {
> #define BUFFER_SIZE PAGE_SIZE
> #define INVALID_DMA_ADDRESS 0xffffffff
>
> +static struct atmel_spi_pdata at91rm9200_config = {
> + .version = 1,
> + .has_dma_support = false,
> + .has_wdrbt = false,
> +};
> +
> +static struct atmel_spi_pdata at91sam9260_config = {
> + .version = 2,
> + .has_dma_support = false,
> + .has_wdrbt = false,
> +};
> +
> +static struct atmel_spi_pdata at91sam9g45_config = {
> + .version = 2,
> + .has_dma_support = false,
> + .has_wdrbt = true,
> +};
> +
> +static struct atmel_spi_pdata at91sam9x5_config = {
> + .version = 2,
> + .has_dma_support = true,
> + .has_wdrbt = true,
> +};
> +
> +static const struct platform_device_id atmel_spi_devtypes[] = {
> + {
> + .name = "spi-at91rm9200",
> + .driver_data = (unsigned long) &at91rm9200_config,
> + }, {
> + .name = "spi-at91sam9260",
> + .driver_data = (unsigned long) &at91sam9260_config,
> + }, {
> + .name = "spi-at91sam9g45",
> + .driver_data = (unsigned long) &at91sam9g45_config,
> + }, {
> + .name = "spi-at91sam9x5",
> + .driver_data = (unsigned long) &at91sam9x5_config,
> + }, {
> + /* sentinel */
> + }
> +};
> +
> +#if defined(CONFIG_OF)
> +static const struct of_device_id atmel_spi_dt_ids[] = {
> + {
> + .compatible = "atmel,at91rm9200-spi",
> + .data = &at91rm9200_config,
> + } , {
> + .compatible = "atmel,at91sam9260-spi",
> + .data = &at91sam9260_config,
> + } , {
> + .compatible = "atmel,at91sam9g45-spi",
> + .data = &at91sam9g45_config,
> + } , {
> + .compatible = "atmel,at91sam9x5-spi",
> + .data = &at91sam9x5_config,
> + }, {
> + /* sentinel */
use the IP revision register to detect it
IIRC 0xfc
Best Regards,
J.
> + }
> +};
> +MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
> +#endif
> +
> /*
> * Version 2 of the SPI controller has
> * - CR.LASTXFER
> @@ -230,11 +302,12 @@ struct atmel_spi_device {
> * register, but I haven't checked that it exists on all chips, and
> * this is cheaper anyway.
> */
> -static bool atmel_spi_is_v2(void)
> +static bool atmel_spi_is_v2(struct atmel_spi *as)
> {
> - return !cpu_is_at91rm9200();
> + return as->pdata->version == 2;
> }
>
> +
> /*
> * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby
> * they assume that spi slave device state will not change on deselect, so
> @@ -266,15 +339,21 @@ static void cs_activate(struct atmel_spi *as, struct spi_device *spi)
> unsigned active = spi->mode & SPI_CS_HIGH;
> u32 mr;
>
> - if (atmel_spi_is_v2()) {
> + if (atmel_spi_is_v2(as)) {
> /*
> * Always use CSR0. This ensures that the clock
> * switches to the correct idle polarity before we
> * toggle the CS.
> */
> spi_writel(as, CSR0, asd->csr);
> - spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MODFDIS)
> - | SPI_BIT(MSTR));
> +
> + if (as->pdata->has_wdrbt)
> + spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MSTR)
> + | SPI_BIT(MODFDIS) | SPI_BIT(WDRBT));
> + else
> + spi_writel(as, MR, SPI_BF(PCS, 0x0e)
> + | SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
> +
> mr = spi_readl(as, MR);
> gpio_set_value(asd->npcs_pin, active);
> } else {
> @@ -321,7 +400,7 @@ static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi)
> asd->npcs_pin, active ? " (low)" : "",
> mr);
>
> - if (atmel_spi_is_v2() || spi->chip_select != 0)
> + if (atmel_spi_is_v2(as) || spi->chip_select != 0)
> gpio_set_value(asd->npcs_pin, !active);
> }
>
> @@ -734,7 +813,7 @@ static int atmel_spi_setup(struct spi_device *spi)
> }
>
> /* see notes above re chipselect */
> - if (!atmel_spi_is_v2()
> + if (!atmel_spi_is_v2(as)
> && spi->chip_select == 0
> && (spi->mode & SPI_CS_HIGH)) {
> dev_dbg(&spi->dev, "setup: can't be active-high\n");
> @@ -743,7 +822,7 @@ static int atmel_spi_setup(struct spi_device *spi)
>
> /* v1 chips start out at half the peripheral bus speed. */
> bus_hz = clk_get_rate(as->clk);
> - if (!atmel_spi_is_v2())
> + if (!atmel_spi_is_v2(as))
> bus_hz /= 2;
>
> if (spi->max_speed_hz) {
> @@ -817,7 +896,7 @@ static int atmel_spi_setup(struct spi_device *spi)
> "setup: %lu Hz bpw %u mode 0x%x -> csr%d %08x\n",
> bus_hz / scbr, bits, spi->mode, spi->chip_select, csr);
>
> - if (!atmel_spi_is_v2())
> + if (!atmel_spi_is_v2(as))
> spi_writel(as, CSR0 + 4 * spi->chip_select, csr);
>
> return 0;
> @@ -921,6 +1000,21 @@ static void atmel_spi_cleanup(struct spi_device *spi)
> kfree(asd);
> }
>
> +static struct atmel_spi_pdata * __devinit atmel_spi_get_driver_data(
> + struct platform_device *pdev)
> +{
> + if (pdev->dev.of_node) {
> + const struct of_device_id *match;
> + match = of_match_node(atmel_spi_dt_ids, pdev->dev.of_node);
> + if (!match)
> + return NULL;
> + return (struct atmel_spi_pdata *) match->data;
> + }
> +
> + return (struct atmel_spi_pdata *)
> + platform_get_device_id(pdev)->driver_data;
> +}
> +
> /*-------------------------------------------------------------------------*/
>
> static int atmel_spi_probe(struct platform_device *pdev)
> @@ -987,11 +1081,21 @@ static int atmel_spi_probe(struct platform_device *pdev)
> if (ret)
> goto out_unmap_regs;
>
> + as->pdata = atmel_spi_get_driver_data(pdev);
> + if (!as->pdata)
> + goto out_unmap_regs;
> +
> /* Initialize the hardware */
> clk_enable(clk);
> spi_writel(as, CR, SPI_BIT(SWRST));
> spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
> - spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
> +
> + if (as->pdata->has_wdrbt)
> + spi_writel(as, MR,
> + SPI_BIT(MSTR) | SPI_BIT(MODFDIS) | SPI_BIT(WDRBT));
> + else
> + spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS));
> +
> spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS));
> spi_writel(as, CR, SPI_BIT(SPIEN));
>
> @@ -1084,21 +1188,13 @@ static int atmel_spi_resume(struct platform_device *pdev)
> #define atmel_spi_resume NULL
> #endif
>
> -#if defined(CONFIG_OF)
> -static const struct of_device_id atmel_spi_dt_ids[] = {
> - { .compatible = "atmel,at91rm9200-spi" },
> - { /* sentinel */ }
> -};
> -
> -MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
> -#endif
> -
> static struct platform_driver atmel_spi_driver = {
> .driver = {
> .name = "atmel_spi",
> .owner = THIS_MODULE,
> .of_match_table = of_match_ptr(atmel_spi_dt_ids),
> },
> + .id_table = atmel_spi_devtypes,
> .suspend = atmel_spi_suspend,
> .resume = atmel_spi_resume,
> .probe = atmel_spi_probe,
> --
> 1.7.9.5
>
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