| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Renesas RZ/V2M Clocked Serial Interface (CSI) driver |
| * |
| * Copyright (C) 2023 Renesas Electronics Corporation |
| */ |
| |
| #include <linux/bits.h> |
| #include <linux/clk.h> |
| #include <linux/count_zeros.h> |
| #include <linux/interrupt.h> |
| #include <linux/iopoll.h> |
| #include <linux/log2.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/property.h> |
| #include <linux/reset.h> |
| #include <linux/spi/spi.h> |
| #include <linux/units.h> |
| |
| /* Registers */ |
| #define CSI_MODE 0x00 /* CSI mode control */ |
| #define CSI_CLKSEL 0x04 /* CSI clock select */ |
| #define CSI_CNT 0x08 /* CSI control */ |
| #define CSI_INT 0x0C /* CSI interrupt status */ |
| #define CSI_IFIFOL 0x10 /* CSI receive FIFO level display */ |
| #define CSI_OFIFOL 0x14 /* CSI transmit FIFO level display */ |
| #define CSI_IFIFO 0x18 /* CSI receive window */ |
| #define CSI_OFIFO 0x1C /* CSI transmit window */ |
| #define CSI_FIFOTRG 0x20 /* CSI FIFO trigger level */ |
| |
| /* CSI_MODE */ |
| #define CSI_MODE_CSIE BIT(7) |
| #define CSI_MODE_TRMD BIT(6) |
| #define CSI_MODE_CCL BIT(5) |
| #define CSI_MODE_DIR BIT(4) |
| #define CSI_MODE_CSOT BIT(0) |
| |
| #define CSI_MODE_SETUP 0x00000040 |
| |
| /* CSI_CLKSEL */ |
| #define CSI_CLKSEL_SS_ENA BIT(19) |
| #define CSI_CLKSEL_SS_POL BIT(18) |
| #define CSI_CLKSEL_SS (CSI_CLKSEL_SS_ENA | CSI_CLKSEL_SS_POL) |
| #define CSI_CLKSEL_CKP BIT(17) |
| #define CSI_CLKSEL_DAP BIT(16) |
| #define CSI_CLKSEL_MODE (CSI_CLKSEL_CKP|CSI_CLKSEL_DAP) |
| #define CSI_CLKSEL_SLAVE BIT(15) |
| #define CSI_CLKSEL_CKS GENMASK(14, 1) |
| |
| /* CSI_CNT */ |
| #define CSI_CNT_CSIRST BIT(28) |
| #define CSI_CNT_R_TRGEN BIT(19) |
| #define CSI_CNT_UNDER_E BIT(13) |
| #define CSI_CNT_OVERF_E BIT(12) |
| #define CSI_CNT_TREND_E BIT(9) |
| #define CSI_CNT_CSIEND_E BIT(8) |
| #define CSI_CNT_T_TRGR_E BIT(4) |
| #define CSI_CNT_R_TRGR_E BIT(0) |
| |
| /* CSI_INT */ |
| #define CSI_INT_UNDER BIT(13) |
| #define CSI_INT_OVERF BIT(12) |
| #define CSI_INT_TREND BIT(9) |
| #define CSI_INT_CSIEND BIT(8) |
| #define CSI_INT_T_TRGR BIT(4) |
| #define CSI_INT_R_TRGR BIT(0) |
| |
| /* CSI_FIFOTRG */ |
| #define CSI_FIFOTRG_R_TRG GENMASK(2, 0) |
| |
| #define CSI_FIFO_SIZE_BYTES 32U |
| #define CSI_FIFO_HALF_SIZE 16U |
| #define CSI_EN_DIS_TIMEOUT_US 100 |
| /* |
| * Clock "csiclk" gets divided by 2 * CSI_CLKSEL_CKS in order to generate the |
| * serial clock (output from master), with CSI_CLKSEL_CKS ranging from 0x1 (that |
| * means "csiclk" is divided by 2) to 0x3FFF ("csiclk" is divided by 32766). |
| */ |
| #define CSI_CKS_MAX GENMASK(13, 0) |
| |
| #define UNDERRUN_ERROR BIT(0) |
| #define OVERFLOW_ERROR BIT(1) |
| #define TX_TIMEOUT_ERROR BIT(2) |
| #define RX_TIMEOUT_ERROR BIT(3) |
| |
| #define CSI_MAX_SPI_SCKO (8 * HZ_PER_MHZ) |
| |
| #define CSI_CLKSEL_SS_DISABLED 0 |
| #define CSI_CLKSEL_SS_ENABLED_ACTIVE_LOW BIT(1) |
| #define CSI_CLKSEL_SS_ENABLED_ACTIVE_HIGH GENMASK(1, 0) |
| |
| struct rzv2m_csi_priv { |
| void __iomem *base; |
| struct clk *csiclk; |
| struct clk *pclk; |
| struct device *dev; |
| struct spi_controller *controller; |
| const void *txbuf; |
| void *rxbuf; |
| unsigned int buffer_len; |
| unsigned int bytes_sent; |
| unsigned int bytes_received; |
| unsigned int bytes_to_transfer; |
| unsigned int words_to_transfer; |
| unsigned int bytes_per_word; |
| wait_queue_head_t wait; |
| u32 errors; |
| u32 status; |
| bool target_aborted; |
| bool use_ss_pin; |
| }; |
| |
| static void rzv2m_csi_reg_write_bit(const struct rzv2m_csi_priv *csi, |
| int reg_offs, int bit_mask, u32 value) |
| { |
| int nr_zeros; |
| u32 tmp; |
| |
| nr_zeros = count_trailing_zeros(bit_mask); |
| value <<= nr_zeros; |
| |
| tmp = (readl(csi->base + reg_offs) & ~bit_mask) | value; |
| writel(tmp, csi->base + reg_offs); |
| } |
| |
| static int rzv2m_csi_sw_reset(struct rzv2m_csi_priv *csi, int assert) |
| { |
| u32 reg; |
| |
| rzv2m_csi_reg_write_bit(csi, CSI_CNT, CSI_CNT_CSIRST, assert); |
| |
| if (!assert) |
| return 0; |
| |
| return readl_poll_timeout(csi->base + CSI_MODE, reg, |
| !(reg & CSI_MODE_CSOT), 0, |
| CSI_EN_DIS_TIMEOUT_US); |
| } |
| |
| static int rzv2m_csi_start_stop_operation(const struct rzv2m_csi_priv *csi, |
| int enable, bool wait) |
| { |
| u32 reg; |
| |
| rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_CSIE, enable); |
| |
| if (enable || !wait) |
| return 0; |
| |
| return readl_poll_timeout(csi->base + CSI_MODE, reg, |
| !(reg & CSI_MODE_CSOT), 0, |
| CSI_EN_DIS_TIMEOUT_US); |
| } |
| |
| static int rzv2m_csi_fill_txfifo(struct rzv2m_csi_priv *csi) |
| { |
| unsigned int i; |
| |
| if (readl(csi->base + CSI_OFIFOL)) |
| return -EIO; |
| |
| if (csi->bytes_per_word == 2) { |
| const u16 *buf = csi->txbuf; |
| |
| for (i = 0; i < csi->words_to_transfer; i++) |
| writel(buf[i], csi->base + CSI_OFIFO); |
| } else { |
| const u8 *buf = csi->txbuf; |
| |
| for (i = 0; i < csi->words_to_transfer; i++) |
| writel(buf[i], csi->base + CSI_OFIFO); |
| } |
| |
| csi->txbuf += csi->bytes_to_transfer; |
| csi->bytes_sent += csi->bytes_to_transfer; |
| |
| return 0; |
| } |
| |
| static int rzv2m_csi_read_rxfifo(struct rzv2m_csi_priv *csi) |
| { |
| unsigned int i; |
| |
| if (readl(csi->base + CSI_IFIFOL) != csi->bytes_to_transfer) |
| return -EIO; |
| |
| if (csi->bytes_per_word == 2) { |
| u16 *buf = csi->rxbuf; |
| |
| for (i = 0; i < csi->words_to_transfer; i++) |
| buf[i] = (u16)readl(csi->base + CSI_IFIFO); |
| } else { |
| u8 *buf = csi->rxbuf; |
| |
| for (i = 0; i < csi->words_to_transfer; i++) |
| buf[i] = (u8)readl(csi->base + CSI_IFIFO); |
| } |
| |
| csi->rxbuf += csi->bytes_to_transfer; |
| csi->bytes_received += csi->bytes_to_transfer; |
| |
| return 0; |
| } |
| |
| static inline void rzv2m_csi_empty_rxfifo(struct rzv2m_csi_priv *csi) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < csi->words_to_transfer; i++) |
| readl(csi->base + CSI_IFIFO); |
| } |
| |
| static inline void rzv2m_csi_calc_current_transfer(struct rzv2m_csi_priv *csi) |
| { |
| unsigned int bytes_transferred = max(csi->bytes_received, csi->bytes_sent); |
| unsigned int bytes_remaining = csi->buffer_len - bytes_transferred; |
| unsigned int to_transfer; |
| |
| if (csi->txbuf) |
| /* |
| * Leaving a little bit of headroom in the FIFOs makes it very |
| * hard to raise an overflow error (which is only possible |
| * when IP transmits and receives at the same time). |
| */ |
| to_transfer = min(CSI_FIFO_HALF_SIZE, bytes_remaining); |
| else |
| to_transfer = min(CSI_FIFO_SIZE_BYTES, bytes_remaining); |
| |
| if (csi->bytes_per_word == 2) |
| to_transfer >>= 1; |
| |
| /* |
| * We can only choose a trigger level from a predefined set of values. |
| * This will pick a value that is the greatest possible integer that's |
| * less than or equal to the number of bytes we need to transfer. |
| * This may result in multiple smaller transfers. |
| */ |
| csi->words_to_transfer = rounddown_pow_of_two(to_transfer); |
| |
| if (csi->bytes_per_word == 2) |
| csi->bytes_to_transfer = csi->words_to_transfer << 1; |
| else |
| csi->bytes_to_transfer = csi->words_to_transfer; |
| } |
| |
| static inline void rzv2m_csi_set_rx_fifo_trigger_level(struct rzv2m_csi_priv *csi) |
| { |
| rzv2m_csi_reg_write_bit(csi, CSI_FIFOTRG, CSI_FIFOTRG_R_TRG, |
| ilog2(csi->words_to_transfer)); |
| } |
| |
| static inline void rzv2m_csi_enable_rx_trigger(struct rzv2m_csi_priv *csi, |
| bool enable) |
| { |
| rzv2m_csi_reg_write_bit(csi, CSI_CNT, CSI_CNT_R_TRGEN, enable); |
| } |
| |
| static void rzv2m_csi_disable_irqs(const struct rzv2m_csi_priv *csi, |
| u32 enable_bits) |
| { |
| u32 cnt = readl(csi->base + CSI_CNT); |
| |
| writel(cnt & ~enable_bits, csi->base + CSI_CNT); |
| } |
| |
| static void rzv2m_csi_disable_all_irqs(struct rzv2m_csi_priv *csi) |
| { |
| rzv2m_csi_disable_irqs(csi, CSI_CNT_R_TRGR_E | CSI_CNT_T_TRGR_E | |
| CSI_CNT_CSIEND_E | CSI_CNT_TREND_E | |
| CSI_CNT_OVERF_E | CSI_CNT_UNDER_E); |
| } |
| |
| static inline void rzv2m_csi_clear_irqs(struct rzv2m_csi_priv *csi, u32 irqs) |
| { |
| writel(irqs, csi->base + CSI_INT); |
| } |
| |
| static void rzv2m_csi_clear_all_irqs(struct rzv2m_csi_priv *csi) |
| { |
| rzv2m_csi_clear_irqs(csi, CSI_INT_UNDER | CSI_INT_OVERF | |
| CSI_INT_TREND | CSI_INT_CSIEND | CSI_INT_T_TRGR | |
| CSI_INT_R_TRGR); |
| } |
| |
| static void rzv2m_csi_enable_irqs(struct rzv2m_csi_priv *csi, u32 enable_bits) |
| { |
| u32 cnt = readl(csi->base + CSI_CNT); |
| |
| writel(cnt | enable_bits, csi->base + CSI_CNT); |
| } |
| |
| static int rzv2m_csi_wait_for_interrupt(struct rzv2m_csi_priv *csi, |
| u32 wait_mask, u32 enable_bits) |
| { |
| int ret; |
| |
| rzv2m_csi_enable_irqs(csi, enable_bits); |
| |
| if (spi_controller_is_target(csi->controller)) { |
| ret = wait_event_interruptible(csi->wait, |
| ((csi->status & wait_mask) == wait_mask) || |
| csi->errors || csi->target_aborted); |
| if (ret || csi->target_aborted) |
| ret = -EINTR; |
| } else { |
| ret = wait_event_timeout(csi->wait, |
| ((csi->status & wait_mask) == wait_mask) || |
| csi->errors, HZ) == 0 ? -ETIMEDOUT : 0; |
| } |
| |
| rzv2m_csi_disable_irqs(csi, enable_bits); |
| |
| if (csi->errors) |
| return -EIO; |
| |
| return ret; |
| } |
| |
| static inline int rzv2m_csi_wait_for_rx_ready(struct rzv2m_csi_priv *csi) |
| { |
| int ret; |
| |
| if (readl(csi->base + CSI_IFIFOL) >= csi->bytes_to_transfer) |
| return 0; |
| |
| ret = rzv2m_csi_wait_for_interrupt(csi, CSI_INT_R_TRGR, |
| CSI_CNT_R_TRGR_E); |
| if (ret == -ETIMEDOUT) |
| csi->errors |= RX_TIMEOUT_ERROR; |
| |
| return ret; |
| } |
| |
| static irqreturn_t rzv2m_csi_irq_handler(int irq, void *data) |
| { |
| struct rzv2m_csi_priv *csi = data; |
| |
| csi->status = readl(csi->base + CSI_INT); |
| rzv2m_csi_disable_irqs(csi, csi->status); |
| |
| if (csi->status & CSI_INT_OVERF) |
| csi->errors |= OVERFLOW_ERROR; |
| if (csi->status & CSI_INT_UNDER) |
| csi->errors |= UNDERRUN_ERROR; |
| |
| wake_up(&csi->wait); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void rzv2m_csi_setup_clock(struct rzv2m_csi_priv *csi, u32 spi_hz) |
| { |
| unsigned long csiclk_rate = clk_get_rate(csi->csiclk); |
| unsigned long pclk_rate = clk_get_rate(csi->pclk); |
| unsigned long csiclk_rate_limit = pclk_rate >> 1; |
| u32 cks; |
| |
| /* |
| * There is a restriction on the frequency of CSICLK, it has to be <= |
| * PCLK / 2. |
| */ |
| if (csiclk_rate > csiclk_rate_limit) { |
| clk_set_rate(csi->csiclk, csiclk_rate >> 1); |
| csiclk_rate = clk_get_rate(csi->csiclk); |
| } else if ((csiclk_rate << 1) <= csiclk_rate_limit) { |
| clk_set_rate(csi->csiclk, csiclk_rate << 1); |
| csiclk_rate = clk_get_rate(csi->csiclk); |
| } |
| |
| spi_hz = spi_hz > CSI_MAX_SPI_SCKO ? CSI_MAX_SPI_SCKO : spi_hz; |
| |
| cks = DIV_ROUND_UP(csiclk_rate, spi_hz << 1); |
| if (cks > CSI_CKS_MAX) |
| cks = CSI_CKS_MAX; |
| |
| dev_dbg(csi->dev, "SPI clk rate is %ldHz\n", csiclk_rate / (cks << 1)); |
| |
| rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_CKS, cks); |
| } |
| |
| static void rzv2m_csi_setup_operating_mode(struct rzv2m_csi_priv *csi, |
| struct spi_transfer *t) |
| { |
| if (t->rx_buf && !t->tx_buf) |
| /* Reception-only mode */ |
| rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_TRMD, 0); |
| else |
| /* Send and receive mode */ |
| rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_TRMD, 1); |
| |
| csi->bytes_per_word = t->bits_per_word / 8; |
| rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_CCL, |
| csi->bytes_per_word == 2); |
| } |
| |
| static int rzv2m_csi_setup(struct spi_device *spi) |
| { |
| struct rzv2m_csi_priv *csi = spi_controller_get_devdata(spi->controller); |
| u32 slave_selection = CSI_CLKSEL_SS_DISABLED; |
| int ret; |
| |
| rzv2m_csi_sw_reset(csi, 0); |
| |
| writel(CSI_MODE_SETUP, csi->base + CSI_MODE); |
| |
| /* Setup clock polarity and phase timing */ |
| rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_MODE, |
| ~spi->mode & SPI_MODE_X_MASK); |
| |
| /* Setup serial data order */ |
| rzv2m_csi_reg_write_bit(csi, CSI_MODE, CSI_MODE_DIR, |
| !!(spi->mode & SPI_LSB_FIRST)); |
| |
| /* Set the role, 1 for target and 0 for host */ |
| rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_SLAVE, |
| !!spi_controller_is_target(csi->controller)); |
| |
| if (csi->use_ss_pin) |
| slave_selection = spi->mode & SPI_CS_HIGH ? |
| CSI_CLKSEL_SS_ENABLED_ACTIVE_HIGH : |
| CSI_CLKSEL_SS_ENABLED_ACTIVE_LOW; |
| |
| /* Configure the slave selection (SS) pin */ |
| rzv2m_csi_reg_write_bit(csi, CSI_CLKSEL, CSI_CLKSEL_SS, slave_selection); |
| |
| /* Give the IP a SW reset */ |
| ret = rzv2m_csi_sw_reset(csi, 1); |
| if (ret) |
| return ret; |
| rzv2m_csi_sw_reset(csi, 0); |
| |
| /* |
| * We need to enable the communication so that the clock will settle |
| * for the right polarity before enabling the CS. |
| */ |
| rzv2m_csi_start_stop_operation(csi, 1, false); |
| udelay(10); |
| rzv2m_csi_start_stop_operation(csi, 0, false); |
| |
| return 0; |
| } |
| |
| static int rzv2m_csi_pio_transfer(struct rzv2m_csi_priv *csi) |
| { |
| bool tx_completed = !csi->txbuf; |
| bool rx_completed = !csi->rxbuf; |
| int ret = 0; |
| |
| /* Make sure the TX FIFO is empty */ |
| writel(0, csi->base + CSI_OFIFOL); |
| |
| /* Make sure the RX FIFO is empty */ |
| writel(0, csi->base + CSI_IFIFOL); |
| |
| csi->bytes_sent = 0; |
| csi->bytes_received = 0; |
| csi->errors = 0; |
| csi->target_aborted = false; |
| |
| rzv2m_csi_disable_all_irqs(csi); |
| rzv2m_csi_clear_all_irqs(csi); |
| rzv2m_csi_enable_rx_trigger(csi, true); |
| |
| while (!tx_completed || !rx_completed) { |
| /* |
| * Decide how many words we are going to transfer during |
| * this cycle (for both TX and RX), then set the RX FIFO trigger |
| * level accordingly. No need to set a trigger level for the |
| * TX FIFO, as this IP comes with an interrupt that fires when |
| * the TX FIFO is empty. |
| */ |
| rzv2m_csi_calc_current_transfer(csi); |
| rzv2m_csi_set_rx_fifo_trigger_level(csi); |
| |
| rzv2m_csi_enable_irqs(csi, CSI_INT_OVERF | CSI_INT_UNDER); |
| |
| writel(readl(csi->base + CSI_INT), csi->base + CSI_INT); |
| csi->status = 0; |
| |
| /* TX */ |
| if (csi->txbuf) { |
| ret = rzv2m_csi_fill_txfifo(csi); |
| if (ret) |
| break; |
| |
| if (csi->bytes_sent == csi->buffer_len) |
| tx_completed = true; |
| } |
| |
| rzv2m_csi_start_stop_operation(csi, 1, false); |
| |
| /* |
| * Make sure the RX FIFO contains the desired number of words. |
| * We then either flush its content, or we copy it onto |
| * csi->rxbuf. |
| */ |
| ret = rzv2m_csi_wait_for_rx_ready(csi); |
| if (ret) |
| break; |
| |
| if (!spi_controller_is_target(csi->controller)) |
| rzv2m_csi_start_stop_operation(csi, 0, false); |
| |
| /* RX */ |
| if (csi->rxbuf) { |
| ret = rzv2m_csi_read_rxfifo(csi); |
| if (ret) |
| break; |
| |
| if (csi->bytes_received == csi->buffer_len) |
| rx_completed = true; |
| } else { |
| rzv2m_csi_empty_rxfifo(csi); |
| } |
| |
| if (csi->errors) { |
| ret = -EIO; |
| break; |
| } |
| } |
| |
| rzv2m_csi_start_stop_operation(csi, 0, true); |
| rzv2m_csi_disable_all_irqs(csi); |
| rzv2m_csi_enable_rx_trigger(csi, false); |
| rzv2m_csi_clear_all_irqs(csi); |
| |
| return ret; |
| } |
| |
| static int rzv2m_csi_transfer_one(struct spi_controller *controller, |
| struct spi_device *spi, |
| struct spi_transfer *transfer) |
| { |
| struct rzv2m_csi_priv *csi = spi_controller_get_devdata(controller); |
| struct device *dev = csi->dev; |
| int ret; |
| |
| csi->txbuf = transfer->tx_buf; |
| csi->rxbuf = transfer->rx_buf; |
| csi->buffer_len = transfer->len; |
| |
| rzv2m_csi_setup_operating_mode(csi, transfer); |
| |
| if (!spi_controller_is_target(csi->controller)) |
| rzv2m_csi_setup_clock(csi, transfer->speed_hz); |
| |
| ret = rzv2m_csi_pio_transfer(csi); |
| if (ret) { |
| if (csi->errors & UNDERRUN_ERROR) |
| dev_err(dev, "Underrun error\n"); |
| if (csi->errors & OVERFLOW_ERROR) |
| dev_err(dev, "Overflow error\n"); |
| if (csi->errors & TX_TIMEOUT_ERROR) |
| dev_err(dev, "TX timeout error\n"); |
| if (csi->errors & RX_TIMEOUT_ERROR) |
| dev_err(dev, "RX timeout error\n"); |
| } |
| |
| return ret; |
| } |
| |
| static int rzv2m_csi_target_abort(struct spi_controller *ctlr) |
| { |
| struct rzv2m_csi_priv *csi = spi_controller_get_devdata(ctlr); |
| |
| csi->target_aborted = true; |
| wake_up(&csi->wait); |
| |
| return 0; |
| } |
| |
| static int rzv2m_csi_probe(struct platform_device *pdev) |
| { |
| struct device_node *np = pdev->dev.of_node; |
| struct spi_controller *controller; |
| struct device *dev = &pdev->dev; |
| struct rzv2m_csi_priv *csi; |
| struct reset_control *rstc; |
| bool target_mode; |
| int irq; |
| int ret; |
| |
| target_mode = of_property_read_bool(np, "spi-slave"); |
| |
| if (target_mode) |
| controller = devm_spi_alloc_target(dev, sizeof(*csi)); |
| else |
| controller = devm_spi_alloc_host(dev, sizeof(*csi)); |
| |
| if (!controller) |
| return -ENOMEM; |
| |
| csi = spi_controller_get_devdata(controller); |
| platform_set_drvdata(pdev, csi); |
| |
| csi->use_ss_pin = false; |
| if (spi_controller_is_target(controller) && |
| !of_property_read_bool(np, "renesas,csi-no-ss")) |
| csi->use_ss_pin = true; |
| |
| csi->dev = dev; |
| csi->controller = controller; |
| csi->target_aborted = false; |
| |
| csi->base = devm_platform_ioremap_resource(pdev, 0); |
| if (IS_ERR(csi->base)) |
| return PTR_ERR(csi->base); |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) |
| return irq; |
| |
| csi->csiclk = devm_clk_get(dev, "csiclk"); |
| if (IS_ERR(csi->csiclk)) |
| return dev_err_probe(dev, PTR_ERR(csi->csiclk), |
| "could not get csiclk\n"); |
| |
| csi->pclk = devm_clk_get(dev, "pclk"); |
| if (IS_ERR(csi->pclk)) |
| return dev_err_probe(dev, PTR_ERR(csi->pclk), |
| "could not get pclk\n"); |
| |
| rstc = devm_reset_control_get_shared(dev, NULL); |
| if (IS_ERR(rstc)) |
| return dev_err_probe(dev, PTR_ERR(rstc), "Missing reset ctrl\n"); |
| |
| init_waitqueue_head(&csi->wait); |
| |
| controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH; |
| controller->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8); |
| controller->setup = rzv2m_csi_setup; |
| controller->transfer_one = rzv2m_csi_transfer_one; |
| controller->use_gpio_descriptors = true; |
| controller->target_abort = rzv2m_csi_target_abort; |
| |
| device_set_node(&controller->dev, dev_fwnode(dev)); |
| |
| ret = devm_request_irq(dev, irq, rzv2m_csi_irq_handler, 0, |
| dev_name(dev), csi); |
| if (ret) |
| return dev_err_probe(dev, ret, "cannot request IRQ\n"); |
| |
| /* |
| * The reset also affects other HW that is not under the control |
| * of Linux. Therefore, all we can do is make sure the reset is |
| * deasserted. |
| */ |
| reset_control_deassert(rstc); |
| |
| /* Make sure the IP is in SW reset state */ |
| ret = rzv2m_csi_sw_reset(csi, 1); |
| if (ret) |
| return ret; |
| |
| ret = clk_prepare_enable(csi->csiclk); |
| if (ret) |
| return dev_err_probe(dev, ret, "could not enable csiclk\n"); |
| |
| ret = spi_register_controller(controller); |
| if (ret) { |
| clk_disable_unprepare(csi->csiclk); |
| return dev_err_probe(dev, ret, "register controller failed\n"); |
| } |
| |
| return 0; |
| } |
| |
| static void rzv2m_csi_remove(struct platform_device *pdev) |
| { |
| struct rzv2m_csi_priv *csi = platform_get_drvdata(pdev); |
| |
| spi_unregister_controller(csi->controller); |
| rzv2m_csi_sw_reset(csi, 1); |
| clk_disable_unprepare(csi->csiclk); |
| } |
| |
| static const struct of_device_id rzv2m_csi_match[] = { |
| { .compatible = "renesas,rzv2m-csi" }, |
| { /* sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(of, rzv2m_csi_match); |
| |
| static struct platform_driver rzv2m_csi_drv = { |
| .probe = rzv2m_csi_probe, |
| .remove_new = rzv2m_csi_remove, |
| .driver = { |
| .name = "rzv2m_csi", |
| .of_match_table = rzv2m_csi_match, |
| }, |
| }; |
| module_platform_driver(rzv2m_csi_drv); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Fabrizio Castro <castro.fabrizio.jz@renesas.com>"); |
| MODULE_DESCRIPTION("Clocked Serial Interface Driver"); |