diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-atmel.c | 66 |
1 files changed, 50 insertions, 16 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index 656d137db253..af3dbab600d5 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -22,9 +22,8 @@ #include <linux/platform_data/atmel.h> #include <linux/of.h> -#include <asm/io.h> -#include <asm/gpio.h> -#include <mach/cpu.h> +#include <linux/io.h> +#include <linux/gpio.h> /* SPI register offsets */ #define SPI_CR 0x0000 @@ -39,6 +38,7 @@ #define SPI_CSR1 0x0034 #define SPI_CSR2 0x0038 #define SPI_CSR3 0x003c +#define SPI_VERSION 0x00fc #define SPI_RPR 0x0100 #define SPI_RCR 0x0104 #define SPI_TPR 0x0108 @@ -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 @@ -180,6 +182,11 @@ #define spi_writel(port,reg,value) \ __raw_writel((value), (port)->regs + SPI_##reg) +struct atmel_spi_caps { + bool is_spi2; + bool has_wdrbt; + bool has_dma_support; +}; /* * The core SPI transfer engine just talks to a register bank to set up @@ -204,6 +211,8 @@ struct atmel_spi { void *buffer; dma_addr_t buffer_dma; + + struct atmel_spi_caps caps; }; /* Controller-specific per-slave state */ @@ -222,14 +231,10 @@ struct atmel_spi_device { * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) * - SPI_CSRx.CSAAT * - SPI_CSRx.SBCR allows faster clocking - * - * We can determine the controller version by reading the VERSION - * 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->caps.is_spi2; } /* @@ -263,15 +268,20 @@ 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) + if (as->caps.has_wdrbt) { + spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(WDRBT) + | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); + } else { + spi_writel(as, MR, SPI_BF(PCS, 0x0e) | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); + } mr = spi_readl(as, MR); gpio_set_value(asd->npcs_pin, active); } else { @@ -318,7 +328,7 @@ 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); } @@ -719,7 +729,7 @@ 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"); @@ -728,7 +738,7 @@ 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) { @@ -804,7 +814,7 @@ 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; @@ -910,6 +920,23 @@ static void atmel_spi_cleanup(struct spi_device *spi) kfree(asd); } +static inline unsigned int atmel_get_version(struct atmel_spi *as) +{ + return spi_readl(as, VERSION) & 0x00000fff; +} + +static void atmel_get_caps(struct atmel_spi *as) +{ + unsigned int version; + + version = atmel_get_version(as); + dev_info(&as->pdev->dev, "version: 0x%x\n", version); + + as->caps.is_spi2 = version > 0x121; + as->caps.has_wdrbt = version >= 0x210; + as->caps.has_dma_support = version >= 0x212; +} + /*-------------------------------------------------------------------------*/ static int atmel_spi_probe(struct platform_device *pdev) @@ -970,6 +997,8 @@ static int atmel_spi_probe(struct platform_device *pdev) as->irq = irq; as->clk = clk; + atmel_get_caps(as); + ret = request_irq(irq, atmel_spi_interrupt, 0, dev_name(&pdev->dev), master); if (ret) @@ -979,7 +1008,12 @@ static int atmel_spi_probe(struct platform_device *pdev) 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->caps.has_wdrbt) { + spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS) + | SPI_BIT(MSTR)); + } 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)); |