// SPDX-License-Identifier: GPL-2.0+ /* * Application UART driver for: * Freescale STMP37XX/STMP378X * Alphascale ASM9260 * * Author: dmitry pervushin * * Copyright 2014 Oleksij Rempel * Provide Alphascale ASM9260 support. * Copyright 2008-2010 Freescale Semiconductor, Inc. * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "serial_mctrl_gpio.h" #define MXS_AUART_PORTS 5 #define MXS_AUART_FIFO_SIZE 16 #define SET_REG 0x4 #define CLR_REG 0x8 #define TOG_REG 0xc #define AUART_CTRL0 0x00000000 #define AUART_CTRL1 0x00000010 #define AUART_CTRL2 0x00000020 #define AUART_LINECTRL 0x00000030 #define AUART_LINECTRL2 0x00000040 #define AUART_INTR 0x00000050 #define AUART_DATA 0x00000060 #define AUART_STAT 0x00000070 #define AUART_DEBUG 0x00000080 #define AUART_VERSION 0x00000090 #define AUART_AUTOBAUD 0x000000a0 #define AUART_CTRL0_SFTRST (1 << 31) #define AUART_CTRL0_CLKGATE (1 << 30) #define AUART_CTRL0_RXTO_ENABLE (1 << 27) #define AUART_CTRL0_RXTIMEOUT(v) (((v) & 0x7ff) << 16) #define AUART_CTRL0_XFER_COUNT(v) ((v) & 0xffff) #define AUART_CTRL1_XFER_COUNT(v) ((v) & 0xffff) #define AUART_CTRL2_DMAONERR (1 << 26) #define AUART_CTRL2_TXDMAE (1 << 25) #define AUART_CTRL2_RXDMAE (1 << 24) #define AUART_CTRL2_CTSEN (1 << 15) #define AUART_CTRL2_RTSEN (1 << 14) #define AUART_CTRL2_RTS (1 << 11) #define AUART_CTRL2_RXE (1 << 9) #define AUART_CTRL2_TXE (1 << 8) #define AUART_CTRL2_UARTEN (1 << 0) #define AUART_LINECTRL_BAUD_DIV_MAX 0x003fffc0 #define AUART_LINECTRL_BAUD_DIV_MIN 0x000000ec #define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16 #define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000 #define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16) #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT 8 #define AUART_LINECTRL_BAUD_DIVFRAC_MASK 0x00003f00 #define AUART_LINECTRL_BAUD_DIVFRAC(v) (((v) & 0x3f) << 8) #define AUART_LINECTRL_SPS (1 << 7) #define AUART_LINECTRL_WLEN_MASK 0x00000060 #define AUART_LINECTRL_WLEN(v) (((v) & 0x3) << 5) #define AUART_LINECTRL_FEN (1 << 4) #define AUART_LINECTRL_STP2 (1 << 3) #define AUART_LINECTRL_EPS (1 << 2) #define AUART_LINECTRL_PEN (1 << 1) #define AUART_LINECTRL_BRK (1 << 0) #define AUART_INTR_RTIEN (1 << 22) #define AUART_INTR_TXIEN (1 << 21) #define AUART_INTR_RXIEN (1 << 20) #define AUART_INTR_CTSMIEN (1 << 17) #define AUART_INTR_RTIS (1 << 6) #define AUART_INTR_TXIS (1 << 5) #define AUART_INTR_RXIS (1 << 4) #define AUART_INTR_CTSMIS (1 << 1) #define AUART_STAT_BUSY (1 << 29) #define AUART_STAT_CTS (1 << 28) #define AUART_STAT_TXFE (1 << 27) #define AUART_STAT_TXFF (1 << 25) #define AUART_STAT_RXFE (1 << 24) #define AUART_STAT_OERR (1 << 19) #define AUART_STAT_BERR (1 << 18) #define AUART_STAT_PERR (1 << 17) #define AUART_STAT_FERR (1 << 16) #define AUART_STAT_RXCOUNT_MASK 0xffff /* * Start of Alphascale asm9260 defines * This list contains only differences of existing bits * between imx2x and asm9260 */ #define ASM9260_HW_CTRL0 0x0000 /* * RW. Tell the UART to execute the RX DMA Command. The * UART will clear this bit at the end of receive execution. */ #define ASM9260_BM_CTRL0_RXDMA_RUN BIT(28) /* RW. 0 use FIFO for status register; 1 use DMA */ #define ASM9260_BM_CTRL0_RXTO_SOURCE_STATUS BIT(25) /* * RW. RX TIMEOUT Enable. Valid for FIFO and DMA. * Warning: If this bit is set to 0, the RX timeout will not affect receive DMA * operation. If this bit is set to 1, a receive timeout will cause the receive * DMA logic to terminate by filling the remaining DMA bytes with garbage data. */ #define ASM9260_BM_CTRL0_RXTO_ENABLE BIT(24) /* * RW. Receive Timeout Counter Value: number of 8-bit-time to wait before * asserting timeout on the RX input. If the RXFIFO is not empty and the RX * input is idle, then the watchdog counter will decrement each bit-time. Note * 7-bit-time is added to the programmed value, so a value of zero will set * the counter to 7-bit-time, a value of 0x1 gives 15-bit-time and so on. Also * note that the counter is reloaded at the end of each frame, so if the frame * is 10 bits long and the timeout counter value is zero, then timeout will * occur (when FIFO is not empty) even if the RX input is not idle. The default * value is 0x3 (31 bit-time). */ #define ASM9260_BM_CTRL0_RXTO_MASK (0xff << 16) /* TIMEOUT = (100*7+1)*(1/BAUD) */ #define ASM9260_BM_CTRL0_DEFAULT_RXTIMEOUT (20 << 16) /* TX ctrl register */ #define ASM9260_HW_CTRL1 0x0010 /* * RW. Tell the UART to execute the TX DMA Command. The * UART will clear this bit at the end of transmit execution. */ #define ASM9260_BM_CTRL1_TXDMA_RUN BIT(28) #define ASM9260_HW_CTRL2 0x0020 /* * RW. Receive Interrupt FIFO Level Select. * The trigger points for the receive interrupt are as follows: * ONE_EIGHTHS = 0x0 Trigger on FIFO full to at least 2 of 16 entries. * ONE_QUARTER = 0x1 Trigger on FIFO full to at least 4 of 16 entries. * ONE_HALF = 0x2 Trigger on FIFO full to at least 8 of 16 entries. * THREE_QUARTERS = 0x3 Trigger on FIFO full to at least 12 of 16 entries. * SEVEN_EIGHTHS = 0x4 Trigger on FIFO full to at least 14 of 16 entries. */ #define ASM9260_BM_CTRL2_RXIFLSEL (7 << 20) #define ASM9260_BM_CTRL2_DEFAULT_RXIFLSEL (3 << 20) /* RW. Same as RXIFLSEL */ #define ASM9260_BM_CTRL2_TXIFLSEL (7 << 16) #define ASM9260_BM_CTRL2_DEFAULT_TXIFLSEL (2 << 16) /* RW. Set DTR. When this bit is 1, the output is 0. */ #define ASM9260_BM_CTRL2_DTR BIT(10) /* RW. Loop Back Enable */ #define ASM9260_BM_CTRL2_LBE BIT(7) #define ASM9260_BM_CTRL2_PORT_ENABLE BIT(0) #define ASM9260_HW_LINECTRL 0x0030 /* * RW. Stick Parity Select. When bits 1, 2, and 7 of this register are set, the * parity bit is transmitted and checked as a 0. When bits 1 and 7 are set, * and bit 2 is 0, the parity bit is transmitted and checked as a 1. When this * bit is cleared stick parity is disabled. */ #define ASM9260_BM_LCTRL_SPS BIT(7) /* RW. Word length */ #define ASM9260_BM_LCTRL_WLEN (3 << 5) #define ASM9260_BM_LCTRL_CHRL_5 (0 << 5) #define ASM9260_BM_LCTRL_CHRL_6 (1 << 5) #define ASM9260_BM_LCTRL_CHRL_7 (2 << 5) #define ASM9260_BM_LCTRL_CHRL_8 (3 << 5) /* * Interrupt register. * contains the interrupt enables and the interrupt status bits */ #define ASM9260_HW_INTR 0x0040 /* Tx FIFO EMPTY Raw Interrupt enable */ #define ASM9260_BM_INTR_TFEIEN BIT(27) /* Overrun Error Interrupt Enable. */ #define ASM9260_BM_INTR_OEIEN BIT(26) /* Break Error Interrupt Enable. */ #define ASM9260_BM_INTR_BEIEN BIT(25) /* Parity Error Interrupt Enable. */ #define ASM9260_BM_INTR_PEIEN BIT(24) /* Framing Error Interrupt Enable. */ #define ASM9260_BM_INTR_FEIEN BIT(23) /* nUARTDSR Modem Interrupt Enable. */ #define ASM9260_BM_INTR_DSRMIEN BIT(19) /* nUARTDCD Modem Interrupt Enable. */ #define ASM9260_BM_INTR_DCDMIEN BIT(18) /* nUARTRI Modem Interrupt Enable. */ #define ASM9260_BM_INTR_RIMIEN BIT(16) /* Auto-Boud Timeout */ #define ASM9260_BM_INTR_ABTO BIT(13) #define ASM9260_BM_INTR_ABEO BIT(12) /* Tx FIFO EMPTY Raw Interrupt state */ #define ASM9260_BM_INTR_TFEIS BIT(11) /* Overrun Error */ #define ASM9260_BM_INTR_OEIS BIT(10) /* Break Error */ #define ASM9260_BM_INTR_BEIS BIT(9) /* Parity Error */ #define ASM9260_BM_INTR_PEIS BIT(8) /* Framing Error */ #define ASM9260_BM_INTR_FEIS BIT(7) #define ASM9260_BM_INTR_DSRMIS BIT(3) #define ASM9260_BM_INTR_DCDMIS BIT(2) #define ASM9260_BM_INTR_RIMIS BIT(0) /* * RW. In DMA mode, up to 4 Received/Transmit characters can be accessed at a * time. In PIO mode, only one character can be accessed at a time. The status * register contains the receive data flags and valid bits. */ #define ASM9260_HW_DATA 0x0050 #define ASM9260_HW_STAT 0x0060 /* RO. If 1, UARTAPP is present in this product. */ #define ASM9260_BM_STAT_PRESENT BIT(31) /* RO. If 1, HISPEED is present in this product. */ #define ASM9260_BM_STAT_HISPEED BIT(30) /* RO. Receive FIFO Full. */ #define ASM9260_BM_STAT_RXFULL BIT(26) /* RO. The UART Debug Register contains the state of the DMA signals. */ #define ASM9260_HW_DEBUG 0x0070 /* DMA Command Run Status */ #define ASM9260_BM_DEBUG_TXDMARUN BIT(5) #define ASM9260_BM_DEBUG_RXDMARUN BIT(4) /* DMA Command End Status */ #define ASM9260_BM_DEBUG_TXCMDEND BIT(3) #define ASM9260_BM_DEBUG_RXCMDEND BIT(2) /* DMA Request Status */ #define ASM9260_BM_DEBUG_TXDMARQ BIT(1) #define ASM9260_BM_DEBUG_RXDMARQ BIT(0) #define ASM9260_HW_ILPR 0x0080 #define ASM9260_HW_RS485CTRL 0x0090 /* * RW. This bit reverses the polarity of the direction control signal on the RTS * (or DTR) pin. * If 0, The direction control pin will be driven to logic ‘0’ when the * transmitter has data to be sent. It will be driven to logic ‘1’ after the * last bit of data has been transmitted. */ #define ASM9260_BM_RS485CTRL_ONIV BIT(5) /* RW. Enable Auto Direction Control. */ #define ASM9260_BM_RS485CTRL_DIR_CTRL BIT(4) /* * RW. If 0 and DIR_CTRL = 1, pin RTS is used for direction control. * If 1 and DIR_CTRL = 1, pin DTR is used for direction control. */ #define ASM9260_BM_RS485CTRL_PINSEL BIT(3) /* RW. Enable Auto Address Detect (AAD). */ #define ASM9260_BM_RS485CTRL_AADEN BIT(2) /* RW. Disable receiver. */ #define ASM9260_BM_RS485CTRL_RXDIS BIT(1) /* RW. Enable RS-485/EIA-485 Normal Multidrop Mode (NMM) */ #define ASM9260_BM_RS485CTRL_RS485EN BIT(0) #define ASM9260_HW_RS485ADRMATCH 0x00a0 /* Contains the address match value. */ #define ASM9260_BM_RS485ADRMATCH_MASK (0xff << 0) #define ASM9260_HW_RS485DLY 0x00b0 /* * RW. Contains the direction control (RTS or DTR) delay value. This delay time * is in periods of the baud clock. */ #define ASM9260_BM_RS485DLY_MASK (0xff << 0) #define ASM9260_HW_AUTOBAUD 0x00c0 /* WO. Auto-baud time-out interrupt clear bit. */ #define ASM9260_BM_AUTOBAUD_TO_INT_CLR BIT(9) /* WO. End of auto-baud interrupt clear bit. */ #define ASM9260_BM_AUTOBAUD_EO_INT_CLR BIT(8) /* Restart in case of timeout (counter restarts at next UART Rx falling edge) */ #define ASM9260_BM_AUTOBAUD_AUTORESTART BIT(2) /* Auto-baud mode select bit. 0 - Mode 0, 1 - Mode 1. */ #define ASM9260_BM_AUTOBAUD_MODE BIT(1) /* * Auto-baud start (auto-baud is running). Auto-baud run bit. This bit is * automatically cleared after auto-baud completion. */ #define ASM9260_BM_AUTOBAUD_START BIT(0) #define ASM9260_HW_CTRL3 0x00d0 #define ASM9260_BM_CTRL3_OUTCLK_DIV_MASK (0xffff << 16) /* * RW. Provide clk over OUTCLK pin. In case of asm9260 it can be configured on * pins 137 and 144. */ #define ASM9260_BM_CTRL3_MASTERMODE BIT(6) /* RW. Baud Rate Mode: 1 - Enable sync mode. 0 - async mode. */ #define ASM9260_BM_CTRL3_SYNCMODE BIT(4) /* RW. 1 - MSB bit send frist; 0 - LSB bit frist. */ #define ASM9260_BM_CTRL3_MSBF BIT(2) /* RW. 1 - sample rate = 8 x Baudrate; 0 - sample rate = 16 x Baudrate. */ #define ASM9260_BM_CTRL3_BAUD8 BIT(1) /* RW. 1 - Set word length to 9bit. 0 - use ASM9260_BM_LCTRL_WLEN */ #define ASM9260_BM_CTRL3_9BIT BIT(0) #define ASM9260_HW_ISO7816_CTRL 0x00e0 /* RW. Enable High Speed mode. */ #define ASM9260_BM_ISO7816CTRL_HS BIT(12) /* Disable Successive Receive NACK */ #define ASM9260_BM_ISO7816CTRL_DS_NACK BIT(8) #define ASM9260_BM_ISO7816CTRL_MAX_ITER_MASK (0xff << 4) /* Receive NACK Inhibit */ #define ASM9260_BM_ISO7816CTRL_INACK BIT(3) #define ASM9260_BM_ISO7816CTRL_NEG_DATA BIT(2) /* RW. 1 - ISO7816 mode; 0 - USART mode */ #define ASM9260_BM_ISO7816CTRL_ENABLE BIT(0) #define ASM9260_HW_ISO7816_ERRCNT 0x00f0 /* Parity error counter. Will be cleared after reading */ #define ASM9260_BM_ISO7816_NB_ERRORS_MASK (0xff << 0) #define ASM9260_HW_ISO7816_STATUS 0x0100 /* Max number of Repetitions Reached */ #define ASM9260_BM_ISO7816_STAT_ITERATION BIT(0) /* End of Alphascale asm9260 defines */ static struct uart_driver auart_driver; enum mxs_auart_type { IMX23_AUART, IMX28_AUART, ASM9260_AUART, }; struct vendor_data { const u16 *reg_offset; }; enum { REG_CTRL0, REG_CTRL1, REG_CTRL2, REG_LINECTRL, REG_LINECTRL2, REG_INTR, REG_DATA, REG_STAT, REG_DEBUG, REG_VERSION, REG_AUTOBAUD, /* The size of the array - must be last */ REG_ARRAY_SIZE, }; static const u16 mxs_asm9260_offsets[REG_ARRAY_SIZE] = { [REG_CTRL0] = ASM9260_HW_CTRL0, [REG_CTRL1] = ASM9260_HW_CTRL1, [REG_CTRL2] = ASM9260_HW_CTRL2, [REG_LINECTRL] = ASM9260_HW_LINECTRL, [REG_INTR] = ASM9260_HW_INTR, [REG_DATA] = ASM9260_HW_DATA, [REG_STAT] = ASM9260_HW_STAT, [REG_DEBUG] = ASM9260_HW_DEBUG, [REG_AUTOBAUD] = ASM9260_HW_AUTOBAUD, }; static const u16 mxs_stmp37xx_offsets[REG_ARRAY_SIZE] = { [REG_CTRL0] = AUART_CTRL0, [REG_CTRL1] = AUART_CTRL1, [REG_CTRL2] = AUART_CTRL2, [REG_LINECTRL] = AUART_LINECTRL, [REG_LINECTRL2] = AUART_LINECTRL2, [REG_INTR] = AUART_INTR, [REG_DATA] = AUART_DATA, [REG_STAT] = AUART_STAT, [REG_DEBUG] = AUART_DEBUG, [REG_VERSION] = AUART_VERSION, [REG_AUTOBAUD] = AUART_AUTOBAUD, }; static const struct vendor_data vendor_alphascale_asm9260 = { .reg_offset = mxs_asm9260_offsets, }; static const struct vendor_data vendor_freescale_stmp37xx = { .reg_offset = mxs_stmp37xx_offsets, }; struct mxs_auart_port { struct uart_port port; #define MXS_AUART_DMA_ENABLED 0x2 #define MXS_AUART_DMA_TX_SYNC 2 /* bit 2 */ #define MXS_AUART_DMA_RX_READY 3 /* bit 3 */ #define MXS_AUART_RTSCTS 4 /* bit 4 */ unsigned long flags; unsigned int mctrl_prev; enum mxs_auart_type devtype; const struct vendor_data *vendor; struct clk *clk; struct clk *clk_ahb; struct device *dev; /* for DMA */ struct scatterlist tx_sgl; struct dma_chan *tx_dma_chan; void *tx_dma_buf; struct scatterlist rx_sgl; struct dma_chan *rx_dma_chan; void *rx_dma_buf; struct mctrl_gpios *gpios; int gpio_irq[UART_GPIO_MAX]; bool ms_irq_enabled; }; static const struct platform_device_id mxs_auart_devtype[] = { { .name = "mxs-auart-imx23", .driver_data = IMX23_AUART }, { .name = "mxs-auart-imx28", .driver_data = IMX28_AUART }, { .name = "as-auart-asm9260", .driver_data = ASM9260_AUART }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(platform, mxs_auart_devtype); static const struct of_device_id mxs_auart_dt_ids[] = { { .compatible = "fsl,imx28-auart", .data = &mxs_auart_devtype[IMX28_AUART] }, { .compatible = "fsl,imx23-auart", .data = &mxs_auart_devtype[IMX23_AUART] }, { .compatible = "alphascale,asm9260-auart", .data = &mxs_auart_devtype[ASM9260_AUART] }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, mxs_auart_dt_ids); static inline int is_imx28_auart(struct mxs_auart_port *s) { return s->devtype == IMX28_AUART; } static inline int is_asm9260_auart(struct mxs_auart_port *s) { return s->devtype == ASM9260_AUART; } static inline bool auart_dma_enabled(struct mxs_auart_port *s) { return s->flags & MXS_AUART_DMA_ENABLED; } static unsigned int mxs_reg_to_offset(const struct mxs_auart_port *uap, unsigned int reg) { return uap->vendor->reg_offset[reg]; } static unsigned int mxs_read(const struct mxs_auart_port *uap, unsigned int reg) { void __iomem *addr = uap->port.membase + mxs_reg_to_offset(uap, reg); return readl_relaxed(addr); } static void mxs_write(unsigned int val, struct mxs_auart_port *uap, unsigned int reg) { void __iomem *addr = uap->port.membase + mxs_reg_to_offset(uap, reg); writel_relaxed(val, addr); } static void mxs_set(unsigned int val, struct mxs_auart_port *uap, unsigned int reg) { void __iomem *addr = uap->port.membase + mxs_reg_to_offset(uap, reg); writel_relaxed(val, addr + SET_REG); } static void mxs_clr(unsigned int val, struct mxs_auart_port *uap, unsigned int reg) { void __iomem *addr = uap->port.membase + mxs_reg_to_offset(uap, reg); writel_relaxed(val, addr + CLR_REG); } static void mxs_auart_stop_tx(struct uart_port *u); #define to_auart_port(u) container_of(u, struct mxs_auart_port, port) static void mxs_auart_tx_chars(struct mxs_auart_port *s); static void dma_tx_callback(void *param) { struct mxs_auart_port *s = param; struct circ_buf *xmit = &s->port.state->xmit; dma_unmap_sg(s->dev, &s->tx_sgl, 1, DMA_TO_DEVICE); /* clear the bit used to serialize the DMA tx. */ clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); smp_mb__after_atomic(); /* wake up the possible processes. */ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&s->port); mxs_auart_tx_chars(s); } static int mxs_auart_dma_tx(struct mxs_auart_port *s, int size) { struct dma_async_tx_descriptor *desc; struct scatterlist *sgl = &s->tx_sgl; struct dma_chan *channel = s->tx_dma_chan; u32 pio; /* [1] : send PIO. Note, the first pio word is CTRL1. */ pio = AUART_CTRL1_XFER_COUNT(size); desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)&pio, 1, DMA_TRANS_NONE, 0); if (!desc) { dev_err(s->dev, "step 1 error\n"); return -EINVAL; } /* [2] : set DMA buffer. */ sg_init_one(sgl, s->tx_dma_buf, size); dma_map_sg(s->dev, sgl, 1, DMA_TO_DEVICE); desc = dmaengine_prep_slave_sg(channel, sgl, 1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) { dev_err(s->dev, "step 2 error\n"); return -EINVAL; } /* [3] : submit the DMA */ desc->callback = dma_tx_callback; desc->callback_param = s; dmaengine_submit(desc); dma_async_issue_pending(channel); return 0; } static void mxs_auart_tx_chars(struct mxs_auart_port *s) { struct circ_buf *xmit = &s->port.state->xmit; if (auart_dma_enabled(s)) { u32 i = 0; int size; void *buffer = s->tx_dma_buf; if (test_and_set_bit(MXS_AUART_DMA_TX_SYNC, &s->flags)) return; while (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { size = min_t(u32, UART_XMIT_SIZE - i, CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE)); memcpy(buffer + i, xmit->buf + xmit->tail, size); xmit->tail = (xmit->tail + size) & (UART_XMIT_SIZE - 1); i += size; if (i >= UART_XMIT_SIZE) break; } if (uart_tx_stopped(&s->port)) mxs_auart_stop_tx(&s->port); if (i) { mxs_auart_dma_tx(s, i); } else { clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); smp_mb__after_atomic(); } return; } while (!(mxs_read(s, REG_STAT) & AUART_STAT_TXFF)) { if (s->port.x_char) { s->port.icount.tx++; mxs_write(s->port.x_char, s, REG_DATA); s->port.x_char = 0; continue; } if (!uart_circ_empty(xmit) && !uart_tx_stopped(&s->port)) { s->port.icount.tx++; mxs_write(xmit->buf[xmit->tail], s, REG_DATA); xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); } else break; } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&s->port); if (uart_circ_empty(&(s->port.state->xmit))) mxs_clr(AUART_INTR_TXIEN, s, REG_INTR); else mxs_set(AUART_INTR_TXIEN, s, REG_INTR); if (uart_tx_stopped(&s->port)) mxs_auart_stop_tx(&s->port); } static void mxs_auart_rx_char(struct mxs_auart_port *s) { int flag; u32 stat; u8 c; c = mxs_read(s, REG_DATA); stat = mxs_read(s, REG_STAT); flag = TTY_NORMAL; s->port.icount.rx++; if (stat & AUART_STAT_BERR) { s->port.icount.brk++; if (uart_handle_break(&s->port)) goto out; } else if (stat & AUART_STAT_PERR) { s->port.icount.parity++; } else if (stat & AUART_STAT_FERR) { s->port.icount.frame++; } /* * Mask off conditions which should be ingored. */ stat &= s->port.read_status_mask; if (stat & AUART_STAT_BERR) { flag = TTY_BREAK; } else if (stat & AUART_STAT_PERR) flag = TTY_PARITY; else if (stat & AUART_STAT_FERR) flag = TTY_FRAME; if (stat & AUART_STAT_OERR) s->port.icount.overrun++; if (uart_handle_sysrq_char(&s->port, c)) goto out; uart_insert_char(&s->port, stat, AUART_STAT_OERR, c, flag); out: mxs_write(stat, s, REG_STAT); } static void mxs_auart_rx_chars(struct mxs_auart_port *s) { u32 stat = 0; for (;;) { stat = mxs_read(s, REG_STAT); if (stat & AUART_STAT_RXFE) break; mxs_auart_rx_char(s); } mxs_write(stat, s, REG_STAT); tty_flip_buffer_push(&s->port.state->port); } static int mxs_auart_request_port(struct uart_port *u) { return 0; } static int mxs_auart_verify_port(struct uart_port *u, struct serial_struct *ser) { if (u->type != PORT_UNKNOWN && u->type != PORT_IMX) return -EINVAL; return 0; } static void mxs_auart_config_port(struct uart_port *u, int flags) { } static const char *mxs_auart_type(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); return dev_name(s->dev); } static void mxs_auart_release_port(struct uart_port *u) { } static void mxs_auart_set_mctrl(struct uart_port *u, unsigned mctrl) { struct mxs_auart_port *s = to_auart_port(u); u32 ctrl = mxs_read(s, REG_CTRL2); ctrl &= ~(AUART_CTRL2_RTSEN | AUART_CTRL2_RTS); if (mctrl & TIOCM_RTS) { if (uart_cts_enabled(u)) ctrl |= AUART_CTRL2_RTSEN; else ctrl |= AUART_CTRL2_RTS; } mxs_write(ctrl, s, REG_CTRL2); mctrl_gpio_set(s->gpios, mctrl); } #define MCTRL_ANY_DELTA (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS) static u32 mxs_auart_modem_status(struct mxs_auart_port *s, u32 mctrl) { u32 mctrl_diff; mctrl_diff = mctrl ^ s->mctrl_prev; s->mctrl_prev = mctrl; if (mctrl_diff & MCTRL_ANY_DELTA && s->ms_irq_enabled && s->port.state != NULL) { if (mctrl_diff & TIOCM_RI) s->port.icount.rng++; if (mctrl_diff & TIOCM_DSR) s->port.icount.dsr++; if (mctrl_diff & TIOCM_CD) uart_handle_dcd_change(&s->port, mctrl & TIOCM_CD); if (mctrl_diff & TIOCM_CTS) uart_handle_cts_change(&s->port, mctrl & TIOCM_CTS); wake_up_interruptible(&s->port.state->port.delta_msr_wait); } return mctrl; } static u32 mxs_auart_get_mctrl(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); u32 stat = mxs_read(s, REG_STAT); u32 mctrl = 0; if (stat & AUART_STAT_CTS) mctrl |= TIOCM_CTS; return mctrl_gpio_get(s->gpios, &mctrl); } /* * Enable modem status interrupts */ static void mxs_auart_enable_ms(struct uart_port *port) { struct mxs_auart_port *s = to_auart_port(port); /* * Interrupt should not be enabled twice */ if (s->ms_irq_enabled) return; s->ms_irq_enabled = true; if (s->gpio_irq[UART_GPIO_CTS] >= 0) enable_irq(s->gpio_irq[UART_GPIO_CTS]); /* TODO: enable AUART_INTR_CTSMIEN otherwise */ if (s->gpio_irq[UART_GPIO_DSR] >= 0) enable_irq(s->gpio_irq[UART_GPIO_DSR]); if (s->gpio_irq[UART_GPIO_RI] >= 0) enable_irq(s->gpio_irq[UART_GPIO_RI]); if (s->gpio_irq[UART_GPIO_DCD] >= 0) enable_irq(s->gpio_irq[UART_GPIO_DCD]); } /* * Disable modem status interrupts */ static void mxs_auart_disable_ms(struct uart_port *port) { struct mxs_auart_port *s = to_auart_port(port); /* * Interrupt should not be disabled twice */ if (!s->ms_irq_enabled) return; s->ms_irq_enabled = false; if (s->gpio_irq[UART_GPIO_CTS] >= 0) disable_irq(s->gpio_irq[UART_GPIO_CTS]); /* TODO: disable AUART_INTR_CTSMIEN otherwise */ if (s->gpio_irq[UART_GPIO_DSR] >= 0) disable_irq(s->gpio_irq[UART_GPIO_DSR]); if (s->gpio_irq[UART_GPIO_RI] >= 0) disable_irq(s->gpio_irq[UART_GPIO_RI]); if (s->gpio_irq[UART_GPIO_DCD] >= 0) disable_irq(s->gpio_irq[UART_GPIO_DCD]); } static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s); static void dma_rx_callback(void *arg) { struct mxs_auart_port *s = (struct mxs_auart_port *) arg; struct tty_port *port = &s->port.state->port; int count; u32 stat; dma_unmap_sg(s->dev, &s->rx_sgl, 1, DMA_FROM_DEVICE); stat = mxs_read(s, REG_STAT); stat &= ~(AUART_STAT_OERR | AUART_STAT_BERR | AUART_STAT_PERR | AUART_STAT_FERR); count = stat & AUART_STAT_RXCOUNT_MASK; tty_insert_flip_string(port, s->rx_dma_buf, count); mxs_write(stat, s, REG_STAT); tty_flip_buffer_push(port); /* start the next DMA for RX. */ mxs_auart_dma_prep_rx(s); } static int mxs_auart_dma_prep_rx(struct mxs_auart_port *s) { struct dma_async_tx_descriptor *desc; struct scatterlist *sgl = &s->rx_sgl; struct dma_chan *channel = s->rx_dma_chan; u32 pio[1]; /* [1] : send PIO */ pio[0] = AUART_CTRL0_RXTO_ENABLE | AUART_CTRL0_RXTIMEOUT(0x80) | AUART_CTRL0_XFER_COUNT(UART_XMIT_SIZE); desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)pio, 1, DMA_TRANS_NONE, 0); if (!desc) { dev_err(s->dev, "step 1 error\n"); return -EINVAL; } /* [2] : send DMA request */ sg_init_one(sgl, s->rx_dma_buf, UART_XMIT_SIZE); dma_map_sg(s->dev, sgl, 1, DMA_FROM_DEVICE); desc = dmaengine_prep_slave_sg(channel, sgl, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) { dev_err(s->dev, "step 2 error\n"); return -1; } /* [3] : submit the DMA, but do not issue it. */ desc->callback = dma_rx_callback; desc->callback_param = s; dmaengine_submit(desc); dma_async_issue_pending(channel); return 0; } static void mxs_auart_dma_exit_channel(struct mxs_auart_port *s) { if (s->tx_dma_chan) { dma_release_channel(s->tx_dma_chan); s->tx_dma_chan = NULL; } if (s->rx_dma_chan) { dma_release_channel(s->rx_dma_chan); s->rx_dma_chan = NULL; } kfree(s->tx_dma_buf); kfree(s->rx_dma_buf); s->tx_dma_buf = NULL; s->rx_dma_buf = NULL; } static void mxs_auart_dma_exit(struct mxs_auart_port *s) { mxs_clr(AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE | AUART_CTRL2_DMAONERR, s, REG_CTRL2); mxs_auart_dma_exit_channel(s); s->flags &= ~MXS_AUART_DMA_ENABLED; clear_bit(MXS_AUART_DMA_TX_SYNC, &s->flags); clear_bit(MXS_AUART_DMA_RX_READY, &s->flags); } static int mxs_auart_dma_init(struct mxs_auart_port *s) { if (auart_dma_enabled(s)) return 0; /* init for RX */ s->rx_dma_chan = dma_request_slave_channel(s->dev, "rx"); if (!s->rx_dma_chan) goto err_out; s->rx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); if (!s->rx_dma_buf) goto err_out; /* init for TX */ s->tx_dma_chan = dma_request_slave_channel(s->dev, "tx"); if (!s->tx_dma_chan) goto err_out; s->tx_dma_buf = kzalloc(UART_XMIT_SIZE, GFP_KERNEL | GFP_DMA); if (!s->tx_dma_buf) goto err_out; /* set the flags */ s->flags |= MXS_AUART_DMA_ENABLED; dev_dbg(s->dev, "enabled the DMA support."); /* The DMA buffer is now the FIFO the TTY subsystem can use */ s->port.fifosize = UART_XMIT_SIZE; return 0; err_out: mxs_auart_dma_exit_channel(s); return -EINVAL; } #define RTS_AT_AUART() !mctrl_gpio_to_gpiod(s->gpios, UART_GPIO_RTS) #define CTS_AT_AUART() !mctrl_gpio_to_gpiod(s->gpios, UART_GPIO_CTS) static void mxs_auart_settermios(struct uart_port *u, struct ktermios *termios, struct ktermios *old) { struct mxs_auart_port *s = to_auart_port(u); u32 bm, ctrl, ctrl2, div; unsigned int cflag, baud, baud_min, baud_max; cflag = termios->c_cflag; ctrl = AUART_LINECTRL_FEN; ctrl2 = mxs_read(s, REG_CTRL2); /* byte size */ switch (cflag & CSIZE) { case CS5: bm = 0; break; case CS6: bm = 1; break; case CS7: bm = 2; break; case CS8: bm = 3; break; default: return; } ctrl |= AUART_LINECTRL_WLEN(bm); /* parity */ if (cflag & PARENB) { ctrl |= AUART_LINECTRL_PEN; if ((cflag & PARODD) == 0) ctrl |= AUART_LINECTRL_EPS; if (cflag & CMSPAR) ctrl |= AUART_LINECTRL_SPS; } u->read_status_mask = AUART_STAT_OERR; if (termios->c_iflag & INPCK) u->read_status_mask |= AUART_STAT_PERR; if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) u->read_status_mask |= AUART_STAT_BERR; /* * Characters to ignore */ u->ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) u->ignore_status_mask |= AUART_STAT_PERR; if (termios->c_iflag & IGNBRK) { u->ignore_status_mask |= AUART_STAT_BERR; /* * If we're ignoring parity and break indicators, * ignore overruns too (for real raw support). */ if (termios->c_iflag & IGNPAR) u->ignore_status_mask |= AUART_STAT_OERR; } /* * ignore all characters if CREAD is not set */ if (cflag & CREAD) ctrl2 |= AUART_CTRL2_RXE; else ctrl2 &= ~AUART_CTRL2_RXE; /* figure out the stop bits requested */ if (cflag & CSTOPB) ctrl |= AUART_LINECTRL_STP2; /* figure out the hardware flow control settings */ ctrl2 &= ~(AUART_CTRL2_CTSEN | AUART_CTRL2_RTSEN); if (cflag & CRTSCTS) { /* * The DMA has a bug(see errata:2836) in mx23. * So we can not implement the DMA for auart in mx23, * we can only implement the DMA support for auart * in mx28. */ if (is_imx28_auart(s) && test_bit(MXS_AUART_RTSCTS, &s->flags)) { if (!mxs_auart_dma_init(s)) /* enable DMA tranfer */ ctrl2 |= AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE | AUART_CTRL2_DMAONERR; } /* Even if RTS is GPIO line RTSEN can be enabled because * the pinctrl configuration decides about RTS pin function */ ctrl2 |= AUART_CTRL2_RTSEN; if (CTS_AT_AUART()) ctrl2 |= AUART_CTRL2_CTSEN; } /* set baud rate */ if (is_asm9260_auart(s)) { baud = uart_get_baud_rate(u, termios, old, u->uartclk * 4 / 0x3FFFFF, u->uartclk / 16); div = u->uartclk * 4 / baud; } else { baud_min = DIV_ROUND_UP(u->uartclk * 32, AUART_LINECTRL_BAUD_DIV_MAX); baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN; baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max); div = DIV_ROUND_CLOSEST(u->uartclk * 32, baud); } ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6); mxs_write(ctrl, s, REG_LINECTRL); mxs_write(ctrl2, s, REG_CTRL2); uart_update_timeout(u, termios->c_cflag, baud); /* prepare for the DMA RX. */ if (auart_dma_enabled(s) && !test_and_set_bit(MXS_AUART_DMA_RX_READY, &s->flags)) { if (!mxs_auart_dma_prep_rx(s)) { /* Disable the normal RX interrupt. */ mxs_clr(AUART_INTR_RXIEN | AUART_INTR_RTIEN, s, REG_INTR); } else { mxs_auart_dma_exit(s); dev_err(s->dev, "We can not start up the DMA.\n"); } } /* CTS flow-control and modem-status interrupts */ if (UART_ENABLE_MS(u, termios->c_cflag)) mxs_auart_enable_ms(u); else mxs_auart_disable_ms(u); } static void mxs_auart_set_ldisc(struct uart_port *port, struct ktermios *termios) { if (termios->c_line == N_PPS) { port->flags |= UPF_HARDPPS_CD; mxs_auart_enable_ms(port); } else { port->flags &= ~UPF_HARDPPS_CD; } } static irqreturn_t mxs_auart_irq_handle(int irq, void *context) { u32 istat, stat; struct mxs_auart_port *s = context; u32 mctrl_temp = s->mctrl_prev; uart_port_lock(&s->port); stat = mxs_read(s, REG_STAT); istat = mxs_read(s, REG_INTR); /* ack irq */ mxs_clr(istat & (AUART_INTR_RTIS | AUART_INTR_TXIS | AUART_INTR_RXIS | AUART_INTR_CTSMIS), s, REG_INTR); /* * Dealing with GPIO interrupt */ if (irq == s->gpio_irq[UART_GPIO_CTS] || irq == s->gpio_irq[UART_GPIO_DCD] || irq == s->gpio_irq[UART_GPIO_DSR] || irq == s->gpio_irq[UART_GPIO_RI]) mxs_auart_modem_status(s, mctrl_gpio_get(s->gpios, &mctrl_temp)); if (istat & AUART_INTR_CTSMIS) { if (CTS_AT_AUART() && s->ms_irq_enabled) uart_handle_cts_change(&s->port, stat & AUART_STAT_CTS); mxs_clr(AUART_INTR_CTSMIS, s, REG_INTR); istat &= ~AUART_INTR_CTSMIS; } if (istat & (AUART_INTR_RTIS | AUART_INTR_RXIS)) { if (!auart_dma_enabled(s)) mxs_auart_rx_chars(s); istat &= ~(AUART_INTR_RTIS | AUART_INTR_RXIS); } if (istat & AUART_INTR_TXIS) { mxs_auart_tx_chars(s); istat &= ~AUART_INTR_TXIS; } uart_port_unlock(&s->port); return IRQ_HANDLED; } static void mxs_auart_reset_deassert(struct mxs_auart_port *s) { int i; unsigned int reg; mxs_clr(AUART_CTRL0_SFTRST, s, REG_CTRL0); for (i = 0; i < 10000; i++) { reg = mxs_read(s, REG_CTRL0); if (!(reg & AUART_CTRL0_SFTRST)) break; udelay(3); } mxs_clr(AUART_CTRL0_CLKGATE, s, REG_CTRL0); } static void mxs_auart_reset_assert(struct mxs_auart_port *s) { int i; u32 reg; reg = mxs_read(s, REG_CTRL0); /* if already in reset state, keep it untouched */ if (reg & AUART_CTRL0_SFTRST) return; mxs_clr(AUART_CTRL0_CLKGATE, s, REG_CTRL0); mxs_set(AUART_CTRL0_SFTRST, s, REG_CTRL0); for (i = 0; i < 1000; i++) { reg = mxs_read(s, REG_CTRL0); /* reset is finished when the clock is gated */ if (reg & AUART_CTRL0_CLKGATE) return; udelay(10); } dev_err(s->dev, "Failed to reset the unit."); } static int mxs_auart_startup(struct uart_port *u) { int ret; struct mxs_auart_port *s = to_auart_port(u); ret = clk_prepare_enable(s->clk); if (ret) return ret; if (uart_console(u)) { mxs_clr(AUART_CTRL0_CLKGATE, s, REG_CTRL0); } else { /* reset the unit to a well known state */ mxs_auart_reset_assert(s); mxs_auart_reset_deassert(s); } mxs_set(AUART_CTRL2_UARTEN, s, REG_CTRL2); mxs_write(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, s, REG_INTR); /* Reset FIFO size (it could have changed if DMA was enabled) */ u->fifosize = MXS_AUART_FIFO_SIZE; /* * Enable fifo so all four bytes of a DMA word are written to * output (otherwise, only the LSB is written, ie. 1 in 4 bytes) */ mxs_set(AUART_LINECTRL_FEN, s, REG_LINECTRL); /* get initial status of modem lines */ mctrl_gpio_get(s->gpios, &s->mctrl_prev); s->ms_irq_enabled = false; return 0; } static void mxs_auart_shutdown(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); mxs_auart_disable_ms(u); if (auart_dma_enabled(s)) mxs_auart_dma_exit(s); if (uart_console(u)) { mxs_clr(AUART_CTRL2_UARTEN, s, REG_CTRL2); mxs_clr(AUART_INTR_RXIEN | AUART_INTR_RTIEN | AUART_INTR_CTSMIEN, s, REG_INTR); mxs_set(AUART_CTRL0_CLKGATE, s, REG_CTRL0); } else { mxs_auart_reset_assert(s); } clk_disable_unprepare(s->clk); } static unsigned int mxs_auart_tx_empty(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); if ((mxs_read(s, REG_STAT) & (AUART_STAT_TXFE | AUART_STAT_BUSY)) == AUART_STAT_TXFE) return TIOCSER_TEMT; return 0; } static void mxs_auart_start_tx(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); /* enable transmitter */ mxs_set(AUART_CTRL2_TXE, s, REG_CTRL2); mxs_auart_tx_chars(s); } static void mxs_auart_stop_tx(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); mxs_clr(AUART_CTRL2_TXE, s, REG_CTRL2); } static void mxs_auart_stop_rx(struct uart_port *u) { struct mxs_auart_port *s = to_auart_port(u); mxs_clr(AUART_CTRL2_RXE, s, REG_CTRL2); } static void mxs_auart_break_ctl(struct uart_port *u, int ctl) { struct mxs_auart_port *s = to_auart_port(u); if (ctl) mxs_set(AUART_LINECTRL_BRK, s, REG_LINECTRL); else mxs_clr(AUART_LINECTRL_BRK, s, REG_LINECTRL); } static const struct uart_ops mxs_auart_ops = { .tx_empty = mxs_auart_tx_empty, .start_tx = mxs_auart_start_tx, .stop_tx = mxs_auart_stop_tx, .stop_rx = mxs_auart_stop_rx, .enable_ms = mxs_auart_enable_ms, .break_ctl = mxs_auart_break_ctl, .set_mctrl = mxs_auart_set_mctrl, .get_mctrl = mxs_auart_get_mctrl, .startup = mxs_auart_startup, .shutdown = mxs_auart_shutdown, .set_termios = mxs_auart_settermios, .set_ldisc = mxs_auart_set_ldisc, .type = mxs_auart_type, .release_port = mxs_auart_release_port, .request_port = mxs_auart_request_port, .config_port = mxs_auart_config_port, .verify_port = mxs_auart_verify_port, }; static struct mxs_auart_port *auart_port[MXS_AUART_PORTS]; #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE static void mxs_auart_console_putchar(struct uart_port *port, int ch) { struct mxs_auart_port *s = to_auart_port(port); unsigned int to = 1000; while (mxs_read(s, REG_STAT) & AUART_STAT_TXFF) { if (!to--) break; udelay(1); } mxs_write(ch, s, REG_DATA); } static void auart_console_write(struct console *co, const char *str, unsigned int count) { struct mxs_auart_port *s; struct uart_port *port; unsigned int old_ctrl0, old_ctrl2; unsigned int to = 20000; if (co->index >= MXS_AUART_PORTS || co->index < 0) return; s = auart_port[co->index]; port = &s->port; clk_enable(s->clk); /* First save the CR then disable the interrupts */ old_ctrl2 = mxs_read(s, REG_CTRL2); old_ctrl0 = mxs_read(s, REG_CTRL0); mxs_clr(AUART_CTRL0_CLKGATE, s, REG_CTRL0); mxs_set(AUART_CTRL2_UARTEN | AUART_CTRL2_TXE, s, REG_CTRL2); uart_console_write(port, str, count, mxs_auart_console_putchar); /* Finally, wait for transmitter to become empty ... */ while (mxs_read(s, REG_STAT) & AUART_STAT_BUSY) { udelay(1); if (!to--) break; } /* * ... and restore the TCR if we waited long enough for the transmitter * to be idle. This might keep the transmitter enabled although it is * unused, but that is better than to disable it while it is still * transmitting. */ if (!(mxs_read(s, REG_STAT) & AUART_STAT_BUSY)) { mxs_write(old_ctrl0, s, REG_CTRL0); mxs_write(old_ctrl2, s, REG_CTRL2); } clk_disable(s->clk); } static void __init auart_console_get_options(struct mxs_auart_port *s, int *baud, int *parity, int *bits) { struct uart_port *port = &s->port; unsigned int lcr_h, quot; if (!(mxs_read(s, REG_CTRL2) & AUART_CTRL2_UARTEN)) return; lcr_h = mxs_read(s, REG_LINECTRL); *parity = 'n'; if (lcr_h & AUART_LINECTRL_PEN) { if (lcr_h & AUART_LINECTRL_EPS) *parity = 'e'; else *parity = 'o'; } if ((lcr_h & AUART_LINECTRL_WLEN_MASK) == AUART_LINECTRL_WLEN(2)) *bits = 7; else *bits = 8; quot = ((mxs_read(s, REG_LINECTRL) & AUART_LINECTRL_BAUD_DIVINT_MASK)) >> (AUART_LINECTRL_BAUD_DIVINT_SHIFT - 6); quot |= ((mxs_read(s, REG_LINECTRL) & AUART_LINECTRL_BAUD_DIVFRAC_MASK)) >> AUART_LINECTRL_BAUD_DIVFRAC_SHIFT; if (quot == 0) quot = 1; *baud = (port->uartclk << 2) / quot; } static int __init auart_console_setup(struct console *co, char *options) { struct mxs_auart_port *s; int baud = 9600; int bits = 8; int parity = 'n'; int flow = 'n'; int ret; /* * Check whether an invalid uart number has been specified, and * if so, search for the first available port that does have * console support. */ if (co->index == -1 || co->index >= ARRAY_SIZE(auart_port)) co->index = 0; s = auart_port[co->index]; if (!s) return -ENODEV; ret = clk_prepare_enable(s->clk); if (ret) return ret; if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); else auart_console_get_options(s, &baud, &parity, &bits); ret = uart_set_options(&s->port, co, baud, parity, bits, flow); clk_disable_unprepare(s->clk); return ret; } static struct console auart_console = { .name = "ttyAPP", .write = auart_console_write, .device = uart_console_device, .setup = auart_console_setup, .flags = CON_PRINTBUFFER, .index = -1, .data = &auart_driver, }; #endif static struct uart_driver auart_driver = { .owner = THIS_MODULE, .driver_name = "ttyAPP", .dev_name = "ttyAPP", .major = 0, .minor = 0, .nr = MXS_AUART_PORTS, #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE .cons = &auart_console, #endif }; static void mxs_init_regs(struct mxs_auart_port *s) { if (is_asm9260_auart(s)) s->vendor = &vendor_alphascale_asm9260; else s->vendor = &vendor_freescale_stmp37xx; } static int mxs_get_clks(struct mxs_auart_port *s, struct platform_device *pdev) { int err; if (!is_asm9260_auart(s)) { s->clk = devm_clk_get(&pdev->dev, NULL); return PTR_ERR_OR_ZERO(s->clk); } s->clk = devm_clk_get(s->dev, "mod"); if (IS_ERR(s->clk)) { dev_err(s->dev, "Failed to get \"mod\" clk\n"); return PTR_ERR(s->clk); } s->clk_ahb = devm_clk_get(s->dev, "ahb"); if (IS_ERR(s->clk_ahb)) { dev_err(s->dev, "Failed to get \"ahb\" clk\n"); return PTR_ERR(s->clk_ahb); } err = clk_prepare_enable(s->clk_ahb); if (err) { dev_err(s->dev, "Failed to enable ahb_clk!\n"); return err; } err = clk_set_rate(s->clk, clk_get_rate(s->clk_ahb)); if (err) { dev_err(s->dev, "Failed to set rate!\n"); goto disable_clk_ahb; } err = clk_prepare_enable(s->clk); if (err) { dev_err(s->dev, "Failed to enable clk!\n"); goto disable_clk_ahb; } return 0; disable_clk_ahb: clk_disable_unprepare(s->clk_ahb); return err; } /* * This function returns 1 if pdev isn't a device instatiated by dt, 0 if it * could successfully get all information from dt or a negative errno. */ static int serial_mxs_probe_dt(struct mxs_auart_port *s, struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; int ret; if (!np) /* no device tree device */ return 1; ret = of_alias_get_id(np, "serial"); if (ret < 0) { dev_err(&pdev->dev, "failed to get alias id: %d\n", ret); return ret; } s->port.line = ret; if (of_get_property(np, "uart-has-rtscts", NULL) || of_get_property(np, "fsl,uart-has-rtscts", NULL) /* deprecated */) set_bit(MXS_AUART_RTSCTS, &s->flags); return 0; } static int mxs_auart_init_gpios(struct mxs_auart_port *s, struct device *dev) { enum mctrl_gpio_idx i; struct gpio_desc *gpiod; s->gpios = mctrl_gpio_init_noauto(dev, 0); if (IS_ERR(s->gpios)) return PTR_ERR(s->gpios); /* Block (enabled before) DMA option if RTS or CTS is GPIO line */ if (!RTS_AT_AUART() || !CTS_AT_AUART()) { if (test_bit(MXS_AUART_RTSCTS, &s->flags)) dev_warn(dev, "DMA and flow control via gpio may cause some problems. DMA disabled!\n"); clear_bit(MXS_AUART_RTSCTS, &s->flags); } for (i = 0; i < UART_GPIO_MAX; i++) { gpiod = mctrl_gpio_to_gpiod(s->gpios, i); if (gpiod && (gpiod_get_direction(gpiod) == 1)) s->gpio_irq[i] = gpiod_to_irq(gpiod); else s->gpio_irq[i] = -EINVAL; } return 0; } static void mxs_auart_free_gpio_irq(struct mxs_auart_port *s) { enum mctrl_gpio_idx i; for (i = 0; i < UART_GPIO_MAX; i++) if (s->gpio_irq[i] >= 0) free_irq(s->gpio_irq[i], s); } static int mxs_auart_request_gpio_irq(struct mxs_auart_port *s) { int *irq = s->gpio_irq; enum mctrl_gpio_idx i; int err = 0; for (i = 0; (i < UART_GPIO_MAX) && !err; i++) { if (irq[i] < 0) continue; irq_set_status_flags(irq[i], IRQ_NOAUTOEN); err = request_irq(irq[i], mxs_auart_irq_handle, IRQ_TYPE_EDGE_BOTH, dev_name(s->dev), s); if (err) dev_err(s->dev, "%s - Can't get %d irq\n", __func__, irq[i]); } /* * If something went wrong, rollback. * Be careful: i may be unsigned. */ while (err && (i-- > 0)) if (irq[i] >= 0) free_irq(irq[i], s); return err; } static int mxs_auart_probe(struct platform_device *pdev) { const struct of_device_id *of_id = of_match_device(mxs_auart_dt_ids, &pdev->dev); struct mxs_auart_port *s; u32 version; int ret, irq; struct resource *r; s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL); if (!s) return -ENOMEM; s->port.dev = &pdev->dev; s->dev = &pdev->dev; ret = serial_mxs_probe_dt(s, pdev); if (ret > 0) s->port.line = pdev->id < 0 ? 0 : pdev->id; else if (ret < 0) return ret; if (s->port.line >= ARRAY_SIZE(auart_port)) { dev_err(&pdev->dev, "serial%d out of range\n", s->port.line); return -EINVAL; } if (of_id) { pdev->id_entry = of_id->data; s->devtype = pdev->id_entry->driver_data; } ret = mxs_get_clks(s, pdev); if (ret) return ret; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!r) { ret = -ENXIO; goto out_disable_clks; } s->port.mapbase = r->start; s->port.membase = ioremap(r->start, resource_size(r)); if (!s->port.membase) { ret = -ENOMEM; goto out_disable_clks; } s->port.ops = &mxs_auart_ops; s->port.iotype = UPIO_MEM; s->port.fifosize = MXS_AUART_FIFO_SIZE; s->port.uartclk = clk_get_rate(s->clk); s->port.type = PORT_IMX; s->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_MXS_AUART_CONSOLE); mxs_init_regs(s); s->mctrl_prev = 0; irq = platform_get_irq(pdev, 0); if (irq < 0) { ret = irq; goto out_iounmap; } s->port.irq = irq; ret = devm_request_irq(&pdev->dev, irq, mxs_auart_irq_handle, 0, dev_name(&pdev->dev), s); if (ret) goto out_iounmap; platform_set_drvdata(pdev, s); ret = mxs_auart_init_gpios(s, &pdev->dev); if (ret) { dev_err(&pdev->dev, "Failed to initialize GPIOs.\n"); goto out_iounmap; } /* * Get the GPIO lines IRQ */ ret = mxs_auart_request_gpio_irq(s); if (ret) goto out_iounmap; auart_port[s->port.line] = s; mxs_auart_reset_deassert(s); ret = uart_add_one_port(&auart_driver, &s->port); if (ret) goto out_free_qpio_irq; /* ASM9260 don't have version reg */ if (is_asm9260_auart(s)) { dev_info(&pdev->dev, "Found APPUART ASM9260\n"); } else { version = mxs_read(s, REG_VERSION); dev_info(&pdev->dev, "Found APPUART %d.%d.%d\n", (version >> 24) & 0xff, (version >> 16) & 0xff, version & 0xffff); } return 0; out_free_qpio_irq: mxs_auart_free_gpio_irq(s); auart_port[pdev->id] = NULL; out_iounmap: iounmap(s->port.membase); out_disable_clks: if (is_asm9260_auart(s)) { clk_disable_unprepare(s->clk); clk_disable_unprepare(s->clk_ahb); } return ret; } static int mxs_auart_remove(struct platform_device *pdev) { struct mxs_auart_port *s = platform_get_drvdata(pdev); uart_remove_one_port(&auart_driver, &s->port); auart_port[pdev->id] = NULL; mxs_auart_free_gpio_irq(s); iounmap(s->port.membase); if (is_asm9260_auart(s)) { clk_disable_unprepare(s->clk); clk_disable_unprepare(s->clk_ahb); } return 0; } static struct platform_driver mxs_auart_driver = { .probe = mxs_auart_probe, .remove = mxs_auart_remove, .driver = { .name = "mxs-auart", .of_match_table = mxs_auart_dt_ids, }, }; static int __init mxs_auart_init(void) { int r; r = uart_register_driver(&auart_driver); if (r) goto out; r = platform_driver_register(&mxs_auart_driver); if (r) goto out_err; return 0; out_err: uart_unregister_driver(&auart_driver); out: return r; } static void __exit mxs_auart_exit(void) { platform_driver_unregister(&mxs_auart_driver); uart_unregister_driver(&auart_driver); } module_init(mxs_auart_init); module_exit(mxs_auart_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Freescale MXS application uart driver"); MODULE_ALIAS("platform:mxs-auart");