diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-pxa2xx.c | 107 |
1 files changed, 84 insertions, 23 deletions
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index 9e9e0f971e6c..d4d29c594156 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -80,6 +80,73 @@ static bool is_lpss_ssp(const struct driver_data *drv_data) return drv_data->ssp_type == LPSS_SSP; } +static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data) +{ + switch (drv_data->ssp_type) { + default: + return SSCR1_CHANGE_MASK; + } +} + +static u32 +pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data) +{ + switch (drv_data->ssp_type) { + default: + return RX_THRESH_DFLT; + } +} + +static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data) +{ + void __iomem *reg = drv_data->ioaddr; + u32 mask; + + switch (drv_data->ssp_type) { + default: + mask = SSSR_TFL_MASK; + break; + } + + return (read_SSSR(reg) & mask) == mask; +} + +static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data, + u32 *sccr1_reg) +{ + u32 mask; + + switch (drv_data->ssp_type) { + default: + mask = SSCR1_RFT; + break; + } + *sccr1_reg &= ~mask; +} + +static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data, + u32 *sccr1_reg, u32 threshold) +{ + switch (drv_data->ssp_type) { + default: + *sccr1_reg |= SSCR1_RxTresh(threshold); + break; + } +} + +static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data, + u32 clk_div, u8 bits) +{ + switch (drv_data->ssp_type) { + default: + return clk_div + | SSCR0_Motorola + | SSCR0_DataSize(bits > 16 ? bits - 16 : bits) + | SSCR0_SSE + | (bits > 16 ? SSCR0_EDSS : 0); + } +} + /* * Read and write LPSS SSP private registers. Caller must first check that * is_lpss_ssp() returns true before these can be called. @@ -234,7 +301,7 @@ static int null_writer(struct driver_data *drv_data) void __iomem *reg = drv_data->ioaddr; u8 n_bytes = drv_data->n_bytes; - if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK) + if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; @@ -262,7 +329,7 @@ static int u8_writer(struct driver_data *drv_data) { void __iomem *reg = drv_data->ioaddr; - if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK) + if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; @@ -289,7 +356,7 @@ static int u16_writer(struct driver_data *drv_data) { void __iomem *reg = drv_data->ioaddr; - if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK) + if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; @@ -316,7 +383,7 @@ static int u32_writer(struct driver_data *drv_data) { void __iomem *reg = drv_data->ioaddr; - if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK) + if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; @@ -508,8 +575,9 @@ static irqreturn_t interrupt_transfer(struct driver_data *drv_data) * remaining RX bytes. */ if (pxa25x_ssp_comp(drv_data)) { + u32 rx_thre; - sccr1_reg &= ~SSCR1_RFT; + pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg); bytes_left = drv_data->rx_end - drv_data->rx; switch (drv_data->n_bytes) { @@ -519,10 +587,11 @@ static irqreturn_t interrupt_transfer(struct driver_data *drv_data) bytes_left >>= 1; } - if (bytes_left > RX_THRESH_DFLT) - bytes_left = RX_THRESH_DFLT; + rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data); + if (rx_thre > bytes_left) + rx_thre = bytes_left; - sccr1_reg |= SSCR1_RxTresh(bytes_left); + pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre); } write_SSCR1(sccr1_reg, reg); } @@ -613,6 +682,7 @@ static void pump_transfers(unsigned long data) u32 cr1; u32 dma_thresh = drv_data->cur_chip->dma_threshold; u32 dma_burst = drv_data->cur_chip->dma_burst_size; + u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data); /* Get current state information */ message = drv_data->cur_msg; @@ -731,11 +801,7 @@ static void pump_transfers(unsigned long data) "pump_transfers: DMA burst size reduced to match bits_per_word\n"); } - cr0 = clk_div - | SSCR0_Motorola - | SSCR0_DataSize(bits > 16 ? bits - 16 : bits) - | SSCR0_SSE - | (bits > 16 ? SSCR0_EDSS : 0); + cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits); } message->state = RUNNING_STATE; @@ -772,16 +838,15 @@ static void pump_transfers(unsigned long data) } /* see if we need to reload the config registers */ - if ((read_SSCR0(reg) != cr0) - || (read_SSCR1(reg) & SSCR1_CHANGE_MASK) != - (cr1 & SSCR1_CHANGE_MASK)) { + if ((read_SSCR0(reg) != cr0) || + (read_SSCR1(reg) & change_mask) != (cr1 & change_mask)) { /* stop the SSP, and update the other bits */ write_SSCR0(cr0 & ~SSCR0_SSE, reg); if (!pxa25x_ssp_comp(drv_data)) write_SSTO(chip->timeout, reg); /* first set CR1 without interrupt and service enables */ - write_SSCR1(cr1 & SSCR1_CHANGE_MASK, reg); + write_SSCR1(cr1 & change_mask, reg); /* restart the SSP */ write_SSCR0(cr0, reg); @@ -959,12 +1024,8 @@ static int setup(struct spi_device *spi) clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz); chip->speed_hz = spi->max_speed_hz; - chip->cr0 = clk_div - | SSCR0_Motorola - | SSCR0_DataSize(spi->bits_per_word > 16 ? - spi->bits_per_word - 16 : spi->bits_per_word) - | SSCR0_SSE - | (spi->bits_per_word > 16 ? SSCR0_EDSS : 0); + chip->cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, + spi->bits_per_word); chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0) | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0); |