diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-06-10 05:30:17 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-06-10 05:30:17 -0300 |
commit | d635711daa98be86d4c7fd01499c34f566b54ccb (patch) | |
tree | aa5cc3760a27c3d57146498cb82fa549547de06c /drivers/spi/spi-pxa2xx.c | |
parent | c91265cd0efb83778f015b4d4b1129bd2cfd075e (diff) |
Linux-libre 4.6.2-gnu
Diffstat (limited to 'drivers/spi/spi-pxa2xx.c')
-rw-r--r-- | drivers/spi/spi-pxa2xx.c | 153 |
1 files changed, 110 insertions, 43 deletions
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index ab9914ad8..86138e410 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -65,8 +65,6 @@ MODULE_ALIAS("platform:pxa2xx-spi"); #define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24) #define LPSS_CS_CONTROL_SW_MODE BIT(0) #define LPSS_CS_CONTROL_CS_HIGH BIT(1) -#define LPSS_CS_CONTROL_CS_SEL_SHIFT 8 -#define LPSS_CS_CONTROL_CS_SEL_MASK (3 << LPSS_CS_CONTROL_CS_SEL_SHIFT) #define LPSS_CAPS_CS_EN_SHIFT 9 #define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT) @@ -82,6 +80,10 @@ struct lpss_config { u32 rx_threshold; u32 tx_threshold_lo; u32 tx_threshold_hi; + /* Chip select control */ + unsigned cs_sel_shift; + unsigned cs_sel_mask; + unsigned cs_num; }; /* Keep these sorted with enum pxa_ssp_type */ @@ -106,12 +108,25 @@ static const struct lpss_config lpss_platforms[] = { .tx_threshold_lo = 160, .tx_threshold_hi = 224, }, + { /* LPSS_BSW_SSP */ + .offset = 0x400, + .reg_general = 0x08, + .reg_ssp = 0x0c, + .reg_cs_ctrl = 0x18, + .reg_capabilities = -1, + .rx_threshold = 64, + .tx_threshold_lo = 160, + .tx_threshold_hi = 224, + .cs_sel_shift = 2, + .cs_sel_mask = 1 << 2, + .cs_num = 2, + }, { /* LPSS_SPT_SSP */ .offset = 0x200, .reg_general = -1, .reg_ssp = 0x20, .reg_cs_ctrl = 0x24, - .reg_capabilities = 0xfc, + .reg_capabilities = -1, .rx_threshold = 1, .tx_threshold_lo = 32, .tx_threshold_hi = 56, @@ -125,6 +140,8 @@ static const struct lpss_config lpss_platforms[] = { .rx_threshold = 1, .tx_threshold_lo = 16, .tx_threshold_hi = 48, + .cs_sel_shift = 8, + .cs_sel_mask = 3 << 8, }, }; @@ -139,6 +156,7 @@ static bool is_lpss_ssp(const struct driver_data *drv_data) switch (drv_data->ssp_type) { case LPSS_LPT_SSP: case LPSS_BYT_SSP: + case LPSS_BSW_SSP: case LPSS_SPT_SSP: case LPSS_BXT_SSP: return true; @@ -288,37 +306,50 @@ static void lpss_ssp_setup(struct driver_data *drv_data) } } +static void lpss_ssp_select_cs(struct driver_data *drv_data, + const struct lpss_config *config) +{ + u32 value, cs; + + if (!config->cs_sel_mask) + return; + + value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl); + + cs = drv_data->cur_msg->spi->chip_select; + cs <<= config->cs_sel_shift; + if (cs != (value & config->cs_sel_mask)) { + /* + * When switching another chip select output active the + * output must be selected first and wait 2 ssp_clk cycles + * before changing state to active. Otherwise a short + * glitch will occur on the previous chip select since + * output select is latched but state control is not. + */ + value &= ~config->cs_sel_mask; + value |= cs; + __lpss_ssp_write_priv(drv_data, + config->reg_cs_ctrl, value); + ndelay(1000000000 / + (drv_data->master->max_speed_hz / 2)); + } +} + static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable) { const struct lpss_config *config; - u32 value, cs; + u32 value; config = lpss_get_config(drv_data); + if (enable) + lpss_ssp_select_cs(drv_data, config); + value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl); - if (enable) { - cs = drv_data->cur_msg->spi->chip_select; - cs <<= LPSS_CS_CONTROL_CS_SEL_SHIFT; - if (cs != (value & LPSS_CS_CONTROL_CS_SEL_MASK)) { - /* - * When switching another chip select output active - * the output must be selected first and wait 2 ssp_clk - * cycles before changing state to active. Otherwise - * a short glitch will occur on the previous chip - * select since output select is latched but state - * control is not. - */ - value &= ~LPSS_CS_CONTROL_CS_SEL_MASK; - value |= cs; - __lpss_ssp_write_priv(drv_data, - config->reg_cs_ctrl, value); - ndelay(1000000000 / - (drv_data->master->max_speed_hz / 2)); - } + if (enable) value &= ~LPSS_CS_CONTROL_CS_HIGH; - } else { + else value |= LPSS_CS_CONTROL_CS_HIGH; - } __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value); } @@ -496,6 +527,7 @@ static void giveback(struct driver_data *drv_data) { struct spi_transfer* last_transfer; struct spi_message *msg; + unsigned long timeout; msg = drv_data->cur_msg; drv_data->cur_msg = NULL; @@ -508,6 +540,12 @@ static void giveback(struct driver_data *drv_data) if (last_transfer->delay_usecs) udelay(last_transfer->delay_usecs); + /* Wait until SSP becomes idle before deasserting the CS */ + timeout = jiffies + msecs_to_jiffies(10); + while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY && + !time_after(jiffies, timeout)) + cpu_relax(); + /* Drop chip select UNLESS cs_change is true or we are returning * a message with an error, or next message is for another chip */ @@ -572,7 +610,7 @@ static void int_error_stop(struct driver_data *drv_data, const char* msg) static void int_transfer_complete(struct driver_data *drv_data) { - /* Stop SSP */ + /* Clear and disable interrupts */ write_SSSR_CS(drv_data, drv_data->clear_sr); reset_sccr1(drv_data); if (!pxa25x_ssp_comp(drv_data)) @@ -957,8 +995,6 @@ static void pump_transfers(unsigned long data) drv_data->tx_end = drv_data->tx + transfer->len; drv_data->rx = transfer->rx_buf; drv_data->rx_end = drv_data->rx + transfer->len; - drv_data->rx_dma = transfer->rx_dma; - drv_data->tx_dma = transfer->tx_dma; drv_data->len = transfer->len; drv_data->write = drv_data->tx ? chip->write : null_writer; drv_data->read = drv_data->rx ? chip->read : null_reader; @@ -1001,19 +1037,6 @@ static void pump_transfers(unsigned long data) "pump_transfers: DMA burst size reduced to match bits_per_word\n"); } - /* NOTE: PXA25x_SSP _could_ use external clocking ... */ - cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits); - if (!pxa25x_ssp_comp(drv_data)) - dev_dbg(&message->spi->dev, "%u Hz actual, %s\n", - drv_data->master->max_speed_hz - / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)), - chip->enable_dma ? "DMA" : "PIO"); - else - dev_dbg(&message->spi->dev, "%u Hz actual, %s\n", - drv_data->master->max_speed_hz / 2 - / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)), - chip->enable_dma ? "DMA" : "PIO"); - message->state = RUNNING_STATE; drv_data->dma_mapped = 0; @@ -1040,6 +1063,19 @@ static void pump_transfers(unsigned long data) write_SSSR_CS(drv_data, drv_data->clear_sr); } + /* NOTE: PXA25x_SSP _could_ use external clocking ... */ + cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits); + if (!pxa25x_ssp_comp(drv_data)) + dev_dbg(&message->spi->dev, "%u Hz actual, %s\n", + drv_data->master->max_speed_hz + / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)), + drv_data->dma_mapped ? "DMA" : "PIO"); + else + dev_dbg(&message->spi->dev, "%u Hz actual, %s\n", + drv_data->master->max_speed_hz / 2 + / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)), + drv_data->dma_mapped ? "DMA" : "PIO"); + if (is_lpss_ssp(drv_data)) { if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff) != chip->lpss_rx_threshold) @@ -1166,6 +1202,7 @@ static int setup(struct spi_device *spi) break; case LPSS_LPT_SSP: case LPSS_BYT_SSP: + case LPSS_BSW_SSP: case LPSS_SPT_SSP: case LPSS_BXT_SSP: config = lpss_get_config(drv_data); @@ -1313,7 +1350,7 @@ static const struct acpi_device_id pxa2xx_spi_acpi_match[] = { { "INT3430", LPSS_LPT_SSP }, { "INT3431", LPSS_LPT_SSP }, { "80860F0E", LPSS_BYT_SSP }, - { "8086228E", LPSS_BYT_SSP }, + { "8086228E", LPSS_BSW_SSP }, { }, }; MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match); @@ -1347,10 +1384,14 @@ static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = { /* SPT-H */ { PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP }, { PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP }, - /* BXT */ + /* BXT A-Step */ { PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP }, + /* BXT B-Step */ + { PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP }, + { PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP }, + { PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP }, /* APL */ { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP }, @@ -1438,6 +1479,29 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev) } #endif +static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs) +{ + struct driver_data *drv_data = spi_master_get_devdata(master); + + if (has_acpi_companion(&drv_data->pdev->dev)) { + switch (drv_data->ssp_type) { + /* + * For Atoms the ACPI DeviceSelection used by the Windows + * driver starts from 1 instead of 0 so translate it here + * to match what Linux expects. + */ + case LPSS_BYT_SSP: + case LPSS_BSW_SSP: + return cs - 1; + + default: + break; + } + } + + return cs; +} + static int pxa2xx_spi_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1490,6 +1554,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) master->setup = setup; master->transfer_one_message = pxa2xx_spi_transfer_one_message; master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer; + master->fw_translate_cs = pxa2xx_spi_fw_translate_cs; master->auto_runtime_pm = true; drv_data->ssp_type = ssp->type; @@ -1576,6 +1641,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) tmp &= LPSS_CAPS_CS_EN_MASK; tmp >>= LPSS_CAPS_CS_EN_SHIFT; platform_info->num_chipselect = ffz(tmp); + } else if (config->cs_num) { + platform_info->num_chipselect = config->cs_num; } } master->num_chipselect = platform_info->num_chipselect; |