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-rw-r--r--drivers/tty/serial/mxs-auart.c1760
1 files changed, 1760 insertions, 0 deletions
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
new file mode 100644
index 000000000..d21a4f3ef
--- /dev/null
+++ b/drivers/tty/serial/mxs-auart.c
@@ -0,0 +1,1760 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Application UART driver for:
+ * Freescale STMP37XX/STMP378X
+ * Alphascale ASM9260
+ *
+ * Author: dmitry pervushin <dimka@embeddedalley.com>
+ *
+ * Copyright 2014 Oleksij Rempel <linux@rempel-privat.de>
+ * Provide Alphascale ASM9260 support.
+ * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/of_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+
+#include <linux/gpio/consumer.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#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) - 5) & 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 of_device_id mxs_auart_dt_ids[] = {
+ {
+ .compatible = "fsl,imx28-auart",
+ .data = (const void *)IMX28_AUART
+ }, {
+ .compatible = "fsl,imx23-auart",
+ .data = (const void *)IMX23_AUART
+ }, {
+ .compatible = "alphascale,asm9260-auart",
+ .data = (const void *)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,
+ const struct ktermios *old)
+{
+ struct mxs_auart_port *s = to_auart_port(u);
+ u32 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);
+
+ ctrl |= AUART_LINECTRL_WLEN(tty_get_char_size(cflag));
+
+ /* 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;
+ struct mxs_auart_port *s = context;
+ u32 mctrl_temp = s->mctrl_prev;
+ u32 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;
+ }
+
+ 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, unsigned char 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(7))
+ *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;
+}
+
+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)
+{
+ struct device_node *np = pdev->dev.of_node;
+ 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 = 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);
+
+ if (s->port.line >= ARRAY_SIZE(auart_port)) {
+ dev_err(&pdev->dev, "serial%d out of range\n", s->port.line);
+ return -EINVAL;
+ }
+
+ s->devtype = (enum mxs_auart_type)of_device_get_match_data(&pdev->dev);
+
+ 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");