/* * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs * Copyright (C) 2013, Intel Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "spi-pxa2xx.h" MODULE_AUTHOR("Stephen Street"); MODULE_DESCRIPTION("PXA2xx SSP SPI Controller"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:pxa2xx-spi"); #define TIMOUT_DFLT 1000 /* * for testing SSCR1 changes that require SSP restart, basically * everything except the service and interrupt enables, the pxa270 developer * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this * list, but the PXA255 dev man says all bits without really meaning the * service and interrupt enables */ #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \ | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \ | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \ | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \ | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \ | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) #define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \ | QUARK_X1000_SSCR1_EFWR \ | QUARK_X1000_SSCR1_RFT \ | QUARK_X1000_SSCR1_TFT \ | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) #define CE4100_SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \ | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \ | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \ | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \ | CE4100_SSCR1_RFT | CE4100_SSCR1_TFT | SSCR1_MWDS \ | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) #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_CAPS_CS_EN_SHIFT 9 #define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT) #define LPSS_PRIV_CLOCK_GATE 0x38 #define LPSS_PRIV_CLOCK_GATE_CLK_CTL_MASK 0x3 #define LPSS_PRIV_CLOCK_GATE_CLK_CTL_FORCE_ON 0x3 struct lpss_config { /* LPSS offset from drv_data->ioaddr */ unsigned offset; /* Register offsets from drv_data->lpss_base or -1 */ int reg_general; int reg_ssp; int reg_cs_ctrl; int reg_capabilities; /* FIFO thresholds */ 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; /* Quirks */ unsigned cs_clk_stays_gated : 1; }; /* Keep these sorted with enum pxa_ssp_type */ static const struct lpss_config lpss_platforms[] = { { /* LPSS_LPT_SSP */ .offset = 0x800, .reg_general = 0x08, .reg_ssp = 0x0c, .reg_cs_ctrl = 0x18, .reg_capabilities = -1, .rx_threshold = 64, .tx_threshold_lo = 160, .tx_threshold_hi = 224, }, { /* LPSS_BYT_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, }, { /* 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 = -1, .rx_threshold = 1, .tx_threshold_lo = 32, .tx_threshold_hi = 56, }, { /* LPSS_BXT_SSP */ .offset = 0x200, .reg_general = -1, .reg_ssp = 0x20, .reg_cs_ctrl = 0x24, .reg_capabilities = 0xfc, .rx_threshold = 1, .tx_threshold_lo = 16, .tx_threshold_hi = 48, .cs_sel_shift = 8, .cs_sel_mask = 3 << 8, .cs_clk_stays_gated = true, }, { /* LPSS_CNL_SSP */ .offset = 0x200, .reg_general = -1, .reg_ssp = 0x20, .reg_cs_ctrl = 0x24, .reg_capabilities = 0xfc, .rx_threshold = 1, .tx_threshold_lo = 32, .tx_threshold_hi = 56, .cs_sel_shift = 8, .cs_sel_mask = 3 << 8, .cs_clk_stays_gated = true, }, }; static inline const struct lpss_config *lpss_get_config(const struct driver_data *drv_data) { return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP]; } 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: case LPSS_CNL_SSP: return true; default: return false; } } static bool is_quark_x1000_ssp(const struct driver_data *drv_data) { return drv_data->ssp_type == QUARK_X1000_SSP; } static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data) { switch (drv_data->ssp_type) { case QUARK_X1000_SSP: return QUARK_X1000_SSCR1_CHANGE_MASK; case CE4100_SSP: return CE4100_SSCR1_CHANGE_MASK; default: return SSCR1_CHANGE_MASK; } } static u32 pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data) { switch (drv_data->ssp_type) { case QUARK_X1000_SSP: return RX_THRESH_QUARK_X1000_DFLT; case CE4100_SSP: return RX_THRESH_CE4100_DFLT; default: return RX_THRESH_DFLT; } } static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data) { u32 mask; switch (drv_data->ssp_type) { case QUARK_X1000_SSP: mask = QUARK_X1000_SSSR_TFL_MASK; break; case CE4100_SSP: mask = CE4100_SSSR_TFL_MASK; break; default: mask = SSSR_TFL_MASK; break; } return (pxa2xx_spi_read(drv_data, SSSR) & 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) { case QUARK_X1000_SSP: mask = QUARK_X1000_SSCR1_RFT; break; case CE4100_SSP: mask = CE4100_SSCR1_RFT; break; 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) { case QUARK_X1000_SSP: *sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold); break; case CE4100_SSP: *sccr1_reg |= CE4100_SSCR1_RxTresh(threshold); break; 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) { case QUARK_X1000_SSP: return clk_div | QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits) | SSCR0_SSE; 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. */ static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset) { WARN_ON(!drv_data->lpss_base); return readl(drv_data->lpss_base + offset); } static void __lpss_ssp_write_priv(struct driver_data *drv_data, unsigned offset, u32 value) { WARN_ON(!drv_data->lpss_base); writel(value, drv_data->lpss_base + offset); } /* * lpss_ssp_setup - perform LPSS SSP specific setup * @drv_data: pointer to the driver private data * * Perform LPSS SSP specific setup. This function must be called first if * one is going to use LPSS SSP private registers. */ static void lpss_ssp_setup(struct driver_data *drv_data) { const struct lpss_config *config; u32 value; config = lpss_get_config(drv_data); drv_data->lpss_base = drv_data->ioaddr + config->offset; /* Enable software chip select control */ value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl); value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH); value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH; __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value); /* Enable multiblock DMA transfers */ if (drv_data->master_info->enable_dma) { __lpss_ssp_write_priv(drv_data, config->reg_ssp, 1); if (config->reg_general >= 0) { value = __lpss_ssp_read_priv(drv_data, config->reg_general); value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE; __lpss_ssp_write_priv(drv_data, config->reg_general, value); } } } static void lpss_ssp_select_cs(struct spi_device *spi, const struct lpss_config *config) { struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); u32 value, cs; if (!config->cs_sel_mask) return; value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl); cs = 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 spi_device *spi, bool enable) { struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); const struct lpss_config *config; u32 value; config = lpss_get_config(drv_data); if (enable) lpss_ssp_select_cs(spi, config); value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl); if (enable) value &= ~LPSS_CS_CONTROL_CS_HIGH; else value |= LPSS_CS_CONTROL_CS_HIGH; __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value); if (config->cs_clk_stays_gated) { u32 clkgate; /* * Changing CS alone when dynamic clock gating is on won't * actually flip CS at that time. This ruins SPI transfers * that specify delays, or have no data. Toggle the clock mode * to force on briefly to poke the CS pin to move. */ clkgate = __lpss_ssp_read_priv(drv_data, LPSS_PRIV_CLOCK_GATE); value = (clkgate & ~LPSS_PRIV_CLOCK_GATE_CLK_CTL_MASK) | LPSS_PRIV_CLOCK_GATE_CLK_CTL_FORCE_ON; __lpss_ssp_write_priv(drv_data, LPSS_PRIV_CLOCK_GATE, value); __lpss_ssp_write_priv(drv_data, LPSS_PRIV_CLOCK_GATE, clkgate); } } static void cs_assert(struct spi_device *spi) { struct chip_data *chip = spi_get_ctldata(spi); struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); if (drv_data->ssp_type == CE4100_SSP) { pxa2xx_spi_write(drv_data, SSSR, chip->frm); return; } if (chip->cs_control) { chip->cs_control(PXA2XX_CS_ASSERT); return; } if (chip->gpiod_cs) { gpiod_set_value(chip->gpiod_cs, chip->gpio_cs_inverted); return; } if (is_lpss_ssp(drv_data)) lpss_ssp_cs_control(spi, true); } static void cs_deassert(struct spi_device *spi) { struct chip_data *chip = spi_get_ctldata(spi); struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); unsigned long timeout; if (drv_data->ssp_type == CE4100_SSP) return; /* 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(); if (chip->cs_control) { chip->cs_control(PXA2XX_CS_DEASSERT); return; } if (chip->gpiod_cs) { gpiod_set_value(chip->gpiod_cs, !chip->gpio_cs_inverted); return; } if (is_lpss_ssp(drv_data)) lpss_ssp_cs_control(spi, false); } static void pxa2xx_spi_set_cs(struct spi_device *spi, bool level) { if (level) cs_deassert(spi); else cs_assert(spi); } int pxa2xx_spi_flush(struct driver_data *drv_data) { unsigned long limit = loops_per_jiffy << 1; do { while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) pxa2xx_spi_read(drv_data, SSDR); } while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit); write_SSSR_CS(drv_data, SSSR_ROR); return limit; } static int null_writer(struct driver_data *drv_data) { u8 n_bytes = drv_data->n_bytes; if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; pxa2xx_spi_write(drv_data, SSDR, 0); drv_data->tx += n_bytes; return 1; } static int null_reader(struct driver_data *drv_data) { u8 n_bytes = drv_data->n_bytes; while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) && (drv_data->rx < drv_data->rx_end)) { pxa2xx_spi_read(drv_data, SSDR); drv_data->rx += n_bytes; } return drv_data->rx == drv_data->rx_end; } static int u8_writer(struct driver_data *drv_data) { if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx)); ++drv_data->tx; return 1; } static int u8_reader(struct driver_data *drv_data) { while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) && (drv_data->rx < drv_data->rx_end)) { *(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); ++drv_data->rx; } return drv_data->rx == drv_data->rx_end; } static int u16_writer(struct driver_data *drv_data) { if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx)); drv_data->tx += 2; return 1; } static int u16_reader(struct driver_data *drv_data) { while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) && (drv_data->rx < drv_data->rx_end)) { *(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); drv_data->rx += 2; } return drv_data->rx == drv_data->rx_end; } static int u32_writer(struct driver_data *drv_data) { if (pxa2xx_spi_txfifo_full(drv_data) || (drv_data->tx == drv_data->tx_end)) return 0; pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx)); drv_data->tx += 4; return 1; } static int u32_reader(struct driver_data *drv_data) { while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE) && (drv_data->rx < drv_data->rx_end)) { *(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR); drv_data->rx += 4; } return drv_data->rx == drv_data->rx_end; } static void reset_sccr1(struct driver_data *drv_data) { struct chip_data *chip = spi_get_ctldata(drv_data->master->cur_msg->spi); u32 sccr1_reg; sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1; switch (drv_data->ssp_type) { case QUARK_X1000_SSP: sccr1_reg &= ~QUARK_X1000_SSCR1_RFT; break; case CE4100_SSP: sccr1_reg &= ~CE4100_SSCR1_RFT; break; default: sccr1_reg &= ~SSCR1_RFT; break; } sccr1_reg |= chip->threshold; pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg); } static void int_error_stop(struct driver_data *drv_data, const char* msg) { /* Stop and reset SSP */ write_SSSR_CS(drv_data, drv_data->clear_sr); reset_sccr1(drv_data); if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, 0); pxa2xx_spi_flush(drv_data); pxa2xx_spi_write(drv_data, SSCR0, pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); dev_err(&drv_data->pdev->dev, "%s\n", msg); drv_data->master->cur_msg->status = -EIO; spi_finalize_current_transfer(drv_data->master); } static void int_transfer_complete(struct driver_data *drv_data) { /* Clear and disable interrupts */ write_SSSR_CS(drv_data, drv_data->clear_sr); reset_sccr1(drv_data); if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, 0); spi_finalize_current_transfer(drv_data->master); } static irqreturn_t interrupt_transfer(struct driver_data *drv_data) { u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ? drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS; u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask; if (irq_status & SSSR_ROR) { int_error_stop(drv_data, "interrupt_transfer: fifo overrun"); return IRQ_HANDLED; } if (irq_status & SSSR_TINT) { pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT); if (drv_data->read(drv_data)) { int_transfer_complete(drv_data); return IRQ_HANDLED; } } /* Drain rx fifo, Fill tx fifo and prevent overruns */ do { if (drv_data->read(drv_data)) { int_transfer_complete(drv_data); return IRQ_HANDLED; } } while (drv_data->write(drv_data)); if (drv_data->read(drv_data)) { int_transfer_complete(drv_data); return IRQ_HANDLED; } if (drv_data->tx == drv_data->tx_end) { u32 bytes_left; u32 sccr1_reg; sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1); sccr1_reg &= ~SSCR1_TIE; /* * PXA25x_SSP has no timeout, set up rx threshould for the * remaining RX bytes. */ if (pxa25x_ssp_comp(drv_data)) { u32 rx_thre; pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg); bytes_left = drv_data->rx_end - drv_data->rx; switch (drv_data->n_bytes) { case 4: bytes_left >>= 1; case 2: bytes_left >>= 1; } rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data); if (rx_thre > bytes_left) rx_thre = bytes_left; pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre); } pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg); } /* We did something */ return IRQ_HANDLED; } static void handle_bad_msg(struct driver_data *drv_data) { pxa2xx_spi_write(drv_data, SSCR0, pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); pxa2xx_spi_write(drv_data, SSCR1, pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1); if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, 0); write_SSSR_CS(drv_data, drv_data->clear_sr); dev_err(&drv_data->pdev->dev, "bad message state in interrupt handler\n"); } static irqreturn_t ssp_int(int irq, void *dev_id) { struct driver_data *drv_data = dev_id; u32 sccr1_reg; u32 mask = drv_data->mask_sr; u32 status; /* * The IRQ might be shared with other peripherals so we must first * check that are we RPM suspended or not. If we are we assume that * the IRQ was not for us (we shouldn't be RPM suspended when the * interrupt is enabled). */ if (pm_runtime_suspended(&drv_data->pdev->dev)) return IRQ_NONE; /* * If the device is not yet in RPM suspended state and we get an * interrupt that is meant for another device, check if status bits * are all set to one. That means that the device is already * powered off. */ status = pxa2xx_spi_read(drv_data, SSSR); if (status == ~0) return IRQ_NONE; sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1); /* Ignore possible writes if we don't need to write */ if (!(sccr1_reg & SSCR1_TIE)) mask &= ~SSSR_TFS; /* Ignore RX timeout interrupt if it is disabled */ if (!(sccr1_reg & SSCR1_TINTE)) mask &= ~SSSR_TINT; if (!(status & mask)) return IRQ_NONE; pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg & ~drv_data->int_cr1); pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg); if (!drv_data->master->cur_msg) { handle_bad_msg(drv_data); /* Never fail */ return IRQ_HANDLED; } return drv_data->transfer_handler(drv_data); } /* * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply * input frequency by fractions of 2^24. It also has a divider by 5. * * There are formulas to get baud rate value for given input frequency and * divider parameters, such as DDS_CLK_RATE and SCR: * * Fsys = 200MHz * * Fssp = Fsys * DDS_CLK_RATE / 2^24 (1) * Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2) * * DDS_CLK_RATE either 2^n or 2^n / 5. * SCR is in range 0 .. 255 * * Divisor = 5^i * 2^j * 2 * k * i = [0, 1] i = 1 iff j = 0 or j > 3 * j = [0, 23] j = 0 iff i = 1 * k = [1, 256] * Special case: j = 0, i = 1: Divisor = 2 / 5 * * Accordingly to the specification the recommended values for DDS_CLK_RATE * are: * Case 1: 2^n, n = [0, 23] * Case 2: 2^24 * 2 / 5 (0x666666) * Case 3: less than or equal to 2^24 / 5 / 16 (0x33333) * * In all cases the lowest possible value is better. * * The function calculates parameters for all cases and chooses the one closest * to the asked baud rate. */ static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds) { unsigned long xtal = 200000000; unsigned long fref = xtal / 2; /* mandatory division by 2, see (2) */ /* case 3 */ unsigned long fref1 = fref / 2; /* case 1 */ unsigned long fref2 = fref * 2 / 5; /* case 2 */ unsigned long scale; unsigned long q, q1, q2; long r, r1, r2; u32 mul; /* Case 1 */ /* Set initial value for DDS_CLK_RATE */ mul = (1 << 24) >> 1; /* Calculate initial quot */ q1 = DIV_ROUND_UP(fref1, rate); /* Scale q1 if it's too big */ if (q1 > 256) { /* Scale q1 to range [1, 512] */ scale = fls_long(q1 - 1); if (scale > 9) { q1 >>= scale - 9; mul >>= scale - 9; } /* Round the result if we have a remainder */ q1 += q1 & 1; } /* Decrease DDS_CLK_RATE as much as we can without loss in precision */ scale = __ffs(q1); q1 >>= scale; mul >>= scale; /* Get the remainder */ r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate); /* Case 2 */ q2 = DIV_ROUND_UP(fref2, rate); r2 = abs(fref2 / q2 - rate); /* * Choose the best between two: less remainder we have the better. We * can't go case 2 if q2 is greater than 256 since SCR register can * hold only values 0 .. 255. */ if (r2 >= r1 || q2 > 256) { /* case 1 is better */ r = r1; q = q1; } else { /* case 2 is better */ r = r2; q = q2; mul = (1 << 24) * 2 / 5; } /* Check case 3 only if the divisor is big enough */ if (fref / rate >= 80) { u64 fssp; u32 m; /* Calculate initial quot */ q1 = DIV_ROUND_UP(fref, rate); m = (1 << 24) / q1; /* Get the remainder */ fssp = (u64)fref * m; do_div(fssp, 1 << 24); r1 = abs(fssp - rate); /* Choose this one if it suits better */ if (r1 < r) { /* case 3 is better */ q = 1; mul = m; } } *dds = mul; return q - 1; } static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate) { unsigned long ssp_clk = drv_data->master->max_speed_hz; const struct ssp_device *ssp = drv_data->ssp; rate = min_t(int, ssp_clk, rate); /* * Calculate the divisor for the SCR (Serial Clock Rate), avoiding * that the SSP transmission rate can be greater than the device rate */ if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP) return (DIV_ROUND_UP(ssp_clk, 2 * rate) - 1) & 0xff; else return (DIV_ROUND_UP(ssp_clk, rate) - 1) & 0xfff; } static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data, int rate) { struct chip_data *chip = spi_get_ctldata(drv_data->master->cur_msg->spi); unsigned int clk_div; switch (drv_data->ssp_type) { case QUARK_X1000_SSP: clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate); break; default: clk_div = ssp_get_clk_div(drv_data, rate); break; } return clk_div << 8; } static bool pxa2xx_spi_can_dma(struct spi_controller *master, struct spi_device *spi, struct spi_transfer *xfer) { struct chip_data *chip = spi_get_ctldata(spi); return chip->enable_dma && xfer->len <= MAX_DMA_LEN && xfer->len >= chip->dma_burst_size; } static int pxa2xx_spi_transfer_one(struct spi_controller *master, struct spi_device *spi, struct spi_transfer *transfer) { struct driver_data *drv_data = spi_controller_get_devdata(master); struct spi_message *message = master->cur_msg; struct chip_data *chip = spi_get_ctldata(message->spi); u32 dma_thresh = chip->dma_threshold; u32 dma_burst = chip->dma_burst_size; u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data); u32 clk_div; u8 bits; u32 speed; u32 cr0; u32 cr1; int err; int dma_mapped; /* Check if we can DMA this transfer */ if (transfer->len > MAX_DMA_LEN && chip->enable_dma) { /* reject already-mapped transfers; PIO won't always work */ if (message->is_dma_mapped || transfer->rx_dma || transfer->tx_dma) { dev_err(&drv_data->pdev->dev, "Mapped transfer length of %u is greater than %d\n", transfer->len, MAX_DMA_LEN); return -EINVAL; } /* warn ... we force this to PIO mode */ dev_warn_ratelimited(&message->spi->dev, "DMA disabled for transfer length %ld greater than %d\n", (long)transfer->len, MAX_DMA_LEN); } /* Setup the transfer state based on the type of transfer */ if (pxa2xx_spi_flush(drv_data) == 0) { dev_err(&drv_data->pdev->dev, "Flush failed\n"); return -EIO; } drv_data->n_bytes = chip->n_bytes; drv_data->tx = (void *)transfer->tx_buf; 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->write = drv_data->tx ? chip->write : null_writer; drv_data->read = drv_data->rx ? chip->read : null_reader; /* Change speed and bit per word on a per transfer */ bits = transfer->bits_per_word; speed = transfer->speed_hz; clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed); if (bits <= 8) { drv_data->n_bytes = 1; drv_data->read = drv_data->read != null_reader ? u8_reader : null_reader; drv_data->write = drv_data->write != null_writer ? u8_writer : null_writer; } else if (bits <= 16) { drv_data->n_bytes = 2; drv_data->read = drv_data->read != null_reader ? u16_reader : null_reader; drv_data->write = drv_data->write != null_writer ? u16_writer : null_writer; } else if (bits <= 32) { drv_data->n_bytes = 4; drv_data->read = drv_data->read != null_reader ? u32_reader : null_reader; drv_data->write = drv_data->write != null_writer ? u32_writer : null_writer; } /* * if bits/word is changed in dma mode, then must check the * thresholds and burst also */ if (chip->enable_dma) { if (pxa2xx_spi_set_dma_burst_and_threshold(chip, message->spi, bits, &dma_burst, &dma_thresh)) dev_warn_ratelimited(&message->spi->dev, "DMA burst size reduced to match bits_per_word\n"); } dma_mapped = master->can_dma && master->can_dma(master, message->spi, transfer) && master->cur_msg_mapped; if (dma_mapped) { /* Ensure we have the correct interrupt handler */ drv_data->transfer_handler = pxa2xx_spi_dma_transfer; err = pxa2xx_spi_dma_prepare(drv_data, transfer); if (err) return err; /* Clear status and start DMA engine */ cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1; pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr); pxa2xx_spi_dma_start(drv_data); } else { /* Ensure we have the correct interrupt handler */ drv_data->transfer_handler = interrupt_transfer; /* Clear status */ cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1; 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", master->max_speed_hz / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)), dma_mapped ? "DMA" : "PIO"); else dev_dbg(&message->spi->dev, "%u Hz actual, %s\n", master->max_speed_hz / 2 / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)), dma_mapped ? "DMA" : "PIO"); if (is_lpss_ssp(drv_data)) { if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff) != chip->lpss_rx_threshold) pxa2xx_spi_write(drv_data, SSIRF, chip->lpss_rx_threshold); if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff) != chip->lpss_tx_threshold) pxa2xx_spi_write(drv_data, SSITF, chip->lpss_tx_threshold); } if (is_quark_x1000_ssp(drv_data) && (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate)) pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate); /* see if we need to reload the config registers */ if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0) || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask) != (cr1 & change_mask)) { /* stop the SSP, and update the other bits */ pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE); if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, chip->timeout); /* first set CR1 without interrupt and service enables */ pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask); /* restart the SSP */ pxa2xx_spi_write(drv_data, SSCR0, cr0); } else { if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, chip->timeout); } /* * Release the data by enabling service requests and interrupts, * without changing any mode bits */ pxa2xx_spi_write(drv_data, SSCR1, cr1); return 1; } static void pxa2xx_spi_handle_err(struct spi_controller *master, struct spi_message *msg) { struct driver_data *drv_data = spi_controller_get_devdata(master); /* Disable the SSP */ pxa2xx_spi_write(drv_data, SSCR0, pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); /* Clear and disable interrupts and service requests */ write_SSSR_CS(drv_data, drv_data->clear_sr); pxa2xx_spi_write(drv_data, SSCR1, pxa2xx_spi_read(drv_data, SSCR1) & ~(drv_data->int_cr1 | drv_data->dma_cr1)); if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, 0); /* * Stop the DMA if running. Note DMA callback handler may have unset * the dma_running already, which is fine as stopping is not needed * then but we shouldn't rely this flag for anything else than * stopping. For instance to differentiate between PIO and DMA * transfers. */ if (atomic_read(&drv_data->dma_running)) pxa2xx_spi_dma_stop(drv_data); } static int pxa2xx_spi_unprepare_transfer(struct spi_controller *master) { struct driver_data *drv_data = spi_controller_get_devdata(master); /* Disable the SSP now */ pxa2xx_spi_write(drv_data, SSCR0, pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); return 0; } static int setup_cs(struct spi_device *spi, struct chip_data *chip, struct pxa2xx_spi_chip *chip_info) { struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); struct gpio_desc *gpiod; int err = 0; if (chip == NULL) return 0; if (drv_data->cs_gpiods) { gpiod = drv_data->cs_gpiods[spi->chip_select]; if (gpiod) { chip->gpiod_cs = gpiod; chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH; gpiod_set_value(gpiod, chip->gpio_cs_inverted); } return 0; } if (chip_info == NULL) return 0; /* NOTE: setup() can be called multiple times, possibly with * different chip_info, release previously requested GPIO */ if (chip->gpiod_cs) { gpiod_put(chip->gpiod_cs); chip->gpiod_cs = NULL; } /* If (*cs_control) is provided, ignore GPIO chip select */ if (chip_info->cs_control) { chip->cs_control = chip_info->cs_control; return 0; } if (gpio_is_valid(chip_info->gpio_cs)) { err = gpio_request(chip_info->gpio_cs, "SPI_CS"); if (err) { dev_err(&spi->dev, "failed to request chip select GPIO%d\n", chip_info->gpio_cs); return err; } gpiod = gpio_to_desc(chip_info->gpio_cs); chip->gpiod_cs = gpiod; chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH; err = gpiod_direction_output(gpiod, !chip->gpio_cs_inverted); } return err; } static int setup(struct spi_device *spi) { struct pxa2xx_spi_chip *chip_info; struct chip_data *chip; const struct lpss_config *config; struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); uint tx_thres, tx_hi_thres, rx_thres; switch (drv_data->ssp_type) { case QUARK_X1000_SSP: tx_thres = TX_THRESH_QUARK_X1000_DFLT; tx_hi_thres = 0; rx_thres = RX_THRESH_QUARK_X1000_DFLT; break; case CE4100_SSP: tx_thres = TX_THRESH_CE4100_DFLT; tx_hi_thres = 0; rx_thres = RX_THRESH_CE4100_DFLT; break; case LPSS_LPT_SSP: case LPSS_BYT_SSP: case LPSS_BSW_SSP: case LPSS_SPT_SSP: case LPSS_BXT_SSP: case LPSS_CNL_SSP: config = lpss_get_config(drv_data); tx_thres = config->tx_threshold_lo; tx_hi_thres = config->tx_threshold_hi; rx_thres = config->rx_threshold; break; default: tx_thres = TX_THRESH_DFLT; tx_hi_thres = 0; rx_thres = RX_THRESH_DFLT; break; } /* Only alloc on first setup */ chip = spi_get_ctldata(spi); if (!chip) { chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL); if (!chip) return -ENOMEM; if (drv_data->ssp_type == CE4100_SSP) { if (spi->chip_select > 4) { dev_err(&spi->dev, "failed setup: cs number must not be > 4.\n"); kfree(chip); return -EINVAL; } chip->frm = spi->chip_select; } chip->enable_dma = drv_data->master_info->enable_dma; chip->timeout = TIMOUT_DFLT; } /* protocol drivers may change the chip settings, so... * if chip_info exists, use it */ chip_info = spi->controller_data; /* chip_info isn't always needed */ chip->cr1 = 0; if (chip_info) { if (chip_info->timeout) chip->timeout = chip_info->timeout; if (chip_info->tx_threshold) tx_thres = chip_info->tx_threshold; if (chip_info->tx_hi_threshold) tx_hi_thres = chip_info->tx_hi_threshold; if (chip_info->rx_threshold) rx_thres = chip_info->rx_threshold; chip->dma_threshold = 0; if (chip_info->enable_loopback) chip->cr1 = SSCR1_LBM; } chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres); chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres) | SSITF_TxHiThresh(tx_hi_thres); /* set dma burst and threshold outside of chip_info path so that if * chip_info goes away after setting chip->enable_dma, the * burst and threshold can still respond to changes in bits_per_word */ if (chip->enable_dma) { /* set up legal burst and threshold for dma */ if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi, spi->bits_per_word, &chip->dma_burst_size, &chip->dma_threshold)) { dev_warn(&spi->dev, "in setup: DMA burst size reduced to match bits_per_word\n"); } } switch (drv_data->ssp_type) { case QUARK_X1000_SSP: chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres) & QUARK_X1000_SSCR1_RFT) | (QUARK_X1000_SSCR1_TxTresh(tx_thres) & QUARK_X1000_SSCR1_TFT); break; case CE4100_SSP: chip->threshold = (CE4100_SSCR1_RxTresh(rx_thres) & CE4100_SSCR1_RFT) | (CE4100_SSCR1_TxTresh(tx_thres) & CE4100_SSCR1_TFT); break; default: chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) | (SSCR1_TxTresh(tx_thres) & SSCR1_TFT); break; } chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0) | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0); if (spi->mode & SPI_LOOP) chip->cr1 |= SSCR1_LBM; if (spi->bits_per_word <= 8) { chip->n_bytes = 1; chip->read = u8_reader; chip->write = u8_writer; } else if (spi->bits_per_word <= 16) { chip->n_bytes = 2; chip->read = u16_reader; chip->write = u16_writer; } else if (spi->bits_per_word <= 32) { chip->n_bytes = 4; chip->read = u32_reader; chip->write = u32_writer; } spi_set_ctldata(spi, chip); if (drv_data->ssp_type == CE4100_SSP) return 0; return setup_cs(spi, chip, chip_info); } static void cleanup(struct spi_device *spi) { struct chip_data *chip = spi_get_ctldata(spi); struct driver_data *drv_data = spi_controller_get_devdata(spi->controller); if (!chip) return; if (drv_data->ssp_type != CE4100_SSP && !drv_data->cs_gpiods && chip->gpiod_cs) gpiod_put(chip->gpiod_cs); kfree(chip); } #ifdef CONFIG_PCI #ifdef CONFIG_ACPI static const struct acpi_device_id pxa2xx_spi_acpi_match[] = { { "INT33C0", LPSS_LPT_SSP }, { "INT33C1", LPSS_LPT_SSP }, { "INT3430", LPSS_LPT_SSP }, { "INT3431", LPSS_LPT_SSP }, { "80860F0E", LPSS_BYT_SSP }, { "8086228E", LPSS_BSW_SSP }, { }, }; MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match); static int pxa2xx_spi_get_port_id(struct acpi_device *adev) { unsigned int devid; int port_id = -1; if (adev && adev->pnp.unique_id && !kstrtouint(adev->pnp.unique_id, 0, &devid)) port_id = devid; return port_id; } #else /* !CONFIG_ACPI */ static int pxa2xx_spi_get_port_id(struct acpi_device *adev) { return -1; } #endif /* * PCI IDs of compound devices that integrate both host controller and private * integrated DMA engine. Please note these are not used in module * autoloading and probing in this module but matching the LPSS SSP type. */ static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = { /* SPT-LP */ { PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP }, { PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP }, /* SPT-H */ { PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP }, { PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP }, /* KBL-H */ { PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP }, { PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP }, /* 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 }, /* GLK */ { PCI_VDEVICE(INTEL, 0x31c2), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x31c4), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x31c6), LPSS_BXT_SSP }, /* ICL-LP */ { PCI_VDEVICE(INTEL, 0x34aa), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0x34ab), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0x34fb), LPSS_CNL_SSP }, /* APL */ { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP }, { PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP }, /* CNL-LP */ { PCI_VDEVICE(INTEL, 0x9daa), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0x9dab), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0x9dfb), LPSS_CNL_SSP }, /* CNL-H */ { PCI_VDEVICE(INTEL, 0xa32a), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0xa32b), LPSS_CNL_SSP }, { PCI_VDEVICE(INTEL, 0xa37b), LPSS_CNL_SSP }, { }, }; static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param) { return param == chan->device->dev; } static struct pxa2xx_spi_master * pxa2xx_spi_init_pdata(struct platform_device *pdev) { struct pxa2xx_spi_master *pdata; struct acpi_device *adev; struct ssp_device *ssp; struct resource *res; const struct acpi_device_id *adev_id = NULL; const struct pci_device_id *pcidev_id = NULL; int type; adev = ACPI_COMPANION(&pdev->dev); if (dev_is_pci(pdev->dev.parent)) pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match, to_pci_dev(pdev->dev.parent)); else if (adev) adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); else return NULL; if (adev_id) type = (int)adev_id->driver_data; else if (pcidev_id) type = (int)pcidev_id->driver_data; else return NULL; pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return NULL; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return NULL; ssp = &pdata->ssp; ssp->phys_base = res->start; ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(ssp->mmio_base)) return NULL; if (pcidev_id) { pdata->tx_param = pdev->dev.parent; pdata->rx_param = pdev->dev.parent; pdata->dma_filter = pxa2xx_spi_idma_filter; } ssp->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(ssp->clk)) return NULL; ssp->irq = platform_get_irq(pdev, 0); if (ssp->irq < 0) return NULL; ssp->type = type; ssp->pdev = pdev; ssp->port_id = pxa2xx_spi_get_port_id(adev); pdata->num_chipselect = 1; pdata->enable_dma = true; return pdata; } #else /* !CONFIG_PCI */ static inline struct pxa2xx_spi_master * pxa2xx_spi_init_pdata(struct platform_device *pdev) { return NULL; } #endif static int pxa2xx_spi_fw_translate_cs(struct spi_controller *master, unsigned int cs) { struct driver_data *drv_data = spi_controller_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; struct pxa2xx_spi_master *platform_info; struct spi_controller *master; struct driver_data *drv_data; struct ssp_device *ssp; const struct lpss_config *config; int status, count; u32 tmp; platform_info = dev_get_platdata(dev); if (!platform_info) { platform_info = pxa2xx_spi_init_pdata(pdev); if (!platform_info) { dev_err(&pdev->dev, "missing platform data\n"); return -ENODEV; } } ssp = pxa_ssp_request(pdev->id, pdev->name); if (!ssp) ssp = &platform_info->ssp; if (!ssp->mmio_base) { dev_err(&pdev->dev, "failed to get ssp\n"); return -ENODEV; } master = devm_spi_alloc_master(dev, sizeof(*drv_data)); if (!master) { dev_err(&pdev->dev, "cannot alloc spi_master\n"); pxa_ssp_free(ssp); return -ENOMEM; } drv_data = spi_controller_get_devdata(master); drv_data->master = master; drv_data->master_info = platform_info; drv_data->pdev = pdev; drv_data->ssp = ssp; master->dev.of_node = pdev->dev.of_node; /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; master->bus_num = ssp->port_id; master->dma_alignment = DMA_ALIGNMENT; master->cleanup = cleanup; master->setup = setup; master->set_cs = pxa2xx_spi_set_cs; master->transfer_one = pxa2xx_spi_transfer_one; master->handle_err = pxa2xx_spi_handle_err; master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer; master->fw_translate_cs = pxa2xx_spi_fw_translate_cs; master->auto_runtime_pm = true; master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX; drv_data->ssp_type = ssp->type; drv_data->ioaddr = ssp->mmio_base; drv_data->ssdr_physical = ssp->phys_base + SSDR; if (pxa25x_ssp_comp(drv_data)) { switch (drv_data->ssp_type) { case QUARK_X1000_SSP: master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); break; default: master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); break; } drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE; drv_data->dma_cr1 = 0; drv_data->clear_sr = SSSR_ROR; drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR; } else { master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE; drv_data->dma_cr1 = DEFAULT_DMA_CR1; drv_data->clear_sr = SSSR_ROR | SSSR_TINT; drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR; } status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev), drv_data); if (status < 0) { dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq); goto out_error_master_alloc; } /* Setup DMA if requested */ if (platform_info->enable_dma) { status = pxa2xx_spi_dma_setup(drv_data); if (status) { dev_dbg(dev, "no DMA channels available, using PIO\n"); platform_info->enable_dma = false; } else { master->can_dma = pxa2xx_spi_can_dma; master->max_dma_len = MAX_DMA_LEN; } } /* Enable SOC clock */ status = clk_prepare_enable(ssp->clk); if (status) goto out_error_dma_irq_alloc; master->max_speed_hz = clk_get_rate(ssp->clk); /* Load default SSP configuration */ pxa2xx_spi_write(drv_data, SSCR0, 0); switch (drv_data->ssp_type) { case QUARK_X1000_SSP: tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) | QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT); pxa2xx_spi_write(drv_data, SSCR1, tmp); /* using the Motorola SPI protocol and use 8 bit frame */ tmp = QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(8); pxa2xx_spi_write(drv_data, SSCR0, tmp); break; case CE4100_SSP: tmp = CE4100_SSCR1_RxTresh(RX_THRESH_CE4100_DFLT) | CE4100_SSCR1_TxTresh(TX_THRESH_CE4100_DFLT); pxa2xx_spi_write(drv_data, SSCR1, tmp); tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8); pxa2xx_spi_write(drv_data, SSCR0, tmp); break; default: tmp = SSCR1_RxTresh(RX_THRESH_DFLT) | SSCR1_TxTresh(TX_THRESH_DFLT); pxa2xx_spi_write(drv_data, SSCR1, tmp); tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8); pxa2xx_spi_write(drv_data, SSCR0, tmp); break; } if (!pxa25x_ssp_comp(drv_data)) pxa2xx_spi_write(drv_data, SSTO, 0); if (!is_quark_x1000_ssp(drv_data)) pxa2xx_spi_write(drv_data, SSPSP, 0); if (is_lpss_ssp(drv_data)) { lpss_ssp_setup(drv_data); config = lpss_get_config(drv_data); if (config->reg_capabilities >= 0) { tmp = __lpss_ssp_read_priv(drv_data, config->reg_capabilities); 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; count = gpiod_count(&pdev->dev, "cs"); if (count > 0) { int i; master->num_chipselect = max_t(int, count, master->num_chipselect); drv_data->cs_gpiods = devm_kcalloc(&pdev->dev, master->num_chipselect, sizeof(struct gpio_desc *), GFP_KERNEL); if (!drv_data->cs_gpiods) { status = -ENOMEM; goto out_error_clock_enabled; } for (i = 0; i < master->num_chipselect; i++) { struct gpio_desc *gpiod; gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS); if (IS_ERR(gpiod)) { /* Means use native chip select */ if (PTR_ERR(gpiod) == -ENOENT) continue; status = (int)PTR_ERR(gpiod); goto out_error_clock_enabled; } else { drv_data->cs_gpiods[i] = gpiod; } } } pm_runtime_set_autosuspend_delay(&pdev->dev, 50); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); /* Register with the SPI framework */ platform_set_drvdata(pdev, drv_data); status = spi_register_controller(master); if (status != 0) { dev_err(&pdev->dev, "problem registering spi master\n"); goto out_error_pm_runtime_enabled; } return status; out_error_pm_runtime_enabled: pm_runtime_disable(&pdev->dev); out_error_clock_enabled: clk_disable_unprepare(ssp->clk); out_error_dma_irq_alloc: pxa2xx_spi_dma_release(drv_data); free_irq(ssp->irq, drv_data); out_error_master_alloc: pxa_ssp_free(ssp); return status; } static int pxa2xx_spi_remove(struct platform_device *pdev) { struct driver_data *drv_data = platform_get_drvdata(pdev); struct ssp_device *ssp; if (!drv_data) return 0; ssp = drv_data->ssp; pm_runtime_get_sync(&pdev->dev); spi_unregister_controller(drv_data->master); /* Disable the SSP at the peripheral and SOC level */ pxa2xx_spi_write(drv_data, SSCR0, 0); clk_disable_unprepare(ssp->clk); /* Release DMA */ if (drv_data->master_info->enable_dma) pxa2xx_spi_dma_release(drv_data); pm_runtime_put_noidle(&pdev->dev); pm_runtime_disable(&pdev->dev); /* Release IRQ */ free_irq(ssp->irq, drv_data); /* Release SSP */ pxa_ssp_free(ssp); return 0; } static void pxa2xx_spi_shutdown(struct platform_device *pdev) { int status = 0; if ((status = pxa2xx_spi_remove(pdev)) != 0) dev_err(&pdev->dev, "shutdown failed with %d\n", status); } #ifdef CONFIG_PM_SLEEP static int pxa2xx_spi_suspend(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); struct ssp_device *ssp = drv_data->ssp; int status; status = spi_controller_suspend(drv_data->master); if (status != 0) return status; pxa2xx_spi_write(drv_data, SSCR0, 0); if (!pm_runtime_suspended(dev)) clk_disable_unprepare(ssp->clk); return 0; } static int pxa2xx_spi_resume(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); struct ssp_device *ssp = drv_data->ssp; int status; /* Enable the SSP clock */ if (!pm_runtime_suspended(dev)) { status = clk_prepare_enable(ssp->clk); if (status) return status; } /* Restore LPSS private register bits */ if (is_lpss_ssp(drv_data)) lpss_ssp_setup(drv_data); /* Start the queue running */ status = spi_controller_resume(drv_data->master); if (status != 0) { dev_err(dev, "problem starting queue (%d)\n", status); return status; } return 0; } #endif #ifdef CONFIG_PM static int pxa2xx_spi_runtime_suspend(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); clk_disable_unprepare(drv_data->ssp->clk); return 0; } static int pxa2xx_spi_runtime_resume(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); int status; status = clk_prepare_enable(drv_data->ssp->clk); return status; } #endif static const struct dev_pm_ops pxa2xx_spi_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume) SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend, pxa2xx_spi_runtime_resume, NULL) }; static struct platform_driver driver = { .driver = { .name = "pxa2xx-spi", .pm = &pxa2xx_spi_pm_ops, .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match), }, .probe = pxa2xx_spi_probe, .remove = pxa2xx_spi_remove, .shutdown = pxa2xx_spi_shutdown, }; static int __init pxa2xx_spi_init(void) { return platform_driver_register(&driver); } subsys_initcall(pxa2xx_spi_init); static void __exit pxa2xx_spi_exit(void) { platform_driver_unregister(&driver); } module_exit(pxa2xx_spi_exit);