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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/tty/serial/omap-serial.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/tty/serial/omap-serial.c')
-rw-r--r--drivers/tty/serial/omap-serial.c1874
1 files changed, 1874 insertions, 0 deletions
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
new file mode 100644
index 000000000..beb7896eb
--- /dev/null
+++ b/drivers/tty/serial/omap-serial.c
@@ -0,0 +1,1874 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for OMAP-UART controller.
+ * Based on drivers/serial/8250.c
+ *
+ * Copyright (C) 2010 Texas Instruments.
+ *
+ * Authors:
+ * Govindraj R <govindraj.raja@ti.com>
+ * Thara Gopinath <thara@ti.com>
+ *
+ * Note: This driver is made separate from 8250 driver as we cannot
+ * over load 8250 driver with omap platform specific configuration for
+ * features like DMA, it makes easier to implement features like DMA and
+ * hardware flow control and software flow control configuration with
+ * this driver as required for the omap-platform.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/serial.h>
+#include <linux/serial_reg.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/serial_core.h>
+#include <linux/irq.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_data/serial-omap.h>
+
+#define OMAP_MAX_HSUART_PORTS 10
+
+#define UART_BUILD_REVISION(x, y) (((x) << 8) | (y))
+
+#define OMAP_UART_REV_42 0x0402
+#define OMAP_UART_REV_46 0x0406
+#define OMAP_UART_REV_52 0x0502
+#define OMAP_UART_REV_63 0x0603
+
+#define OMAP_UART_TX_WAKEUP_EN BIT(7)
+
+/* Feature flags */
+#define OMAP_UART_WER_HAS_TX_WAKEUP BIT(0)
+
+#define UART_ERRATA_i202_MDR1_ACCESS BIT(0)
+#define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1)
+
+#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
+
+/* SCR register bitmasks */
+#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
+#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6)
+#define OMAP_UART_SCR_TX_EMPTY (1 << 3)
+
+/* FCR register bitmasks */
+#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
+#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK (0x3 << 4)
+
+/* MVR register bitmasks */
+#define OMAP_UART_MVR_SCHEME_SHIFT 30
+
+#define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0
+#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4
+#define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f
+
+#define OMAP_UART_MVR_MAJ_MASK 0x700
+#define OMAP_UART_MVR_MAJ_SHIFT 8
+#define OMAP_UART_MVR_MIN_MASK 0x3f
+
+#define OMAP_UART_DMA_CH_FREE -1
+
+#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
+#define OMAP_MODE13X_SPEED 230400
+
+/* WER = 0x7F
+ * Enable module level wakeup in WER reg
+ */
+#define OMAP_UART_WER_MOD_WKUP 0x7F
+
+/* Enable XON/XOFF flow control on output */
+#define OMAP_UART_SW_TX 0x08
+
+/* Enable XON/XOFF flow control on input */
+#define OMAP_UART_SW_RX 0x02
+
+#define OMAP_UART_SW_CLR 0xF0
+
+#define OMAP_UART_TCR_TRIG 0x0F
+
+struct uart_omap_dma {
+ u8 uart_dma_tx;
+ u8 uart_dma_rx;
+ int rx_dma_channel;
+ int tx_dma_channel;
+ dma_addr_t rx_buf_dma_phys;
+ dma_addr_t tx_buf_dma_phys;
+ unsigned int uart_base;
+ /*
+ * Buffer for rx dma. It is not required for tx because the buffer
+ * comes from port structure.
+ */
+ unsigned char *rx_buf;
+ unsigned int prev_rx_dma_pos;
+ int tx_buf_size;
+ int tx_dma_used;
+ int rx_dma_used;
+ spinlock_t tx_lock;
+ spinlock_t rx_lock;
+ /* timer to poll activity on rx dma */
+ struct timer_list rx_timer;
+ unsigned int rx_buf_size;
+ unsigned int rx_poll_rate;
+ unsigned int rx_timeout;
+};
+
+struct uart_omap_port {
+ struct uart_port port;
+ struct uart_omap_dma uart_dma;
+ struct device *dev;
+ int wakeirq;
+
+ unsigned char ier;
+ unsigned char lcr;
+ unsigned char mcr;
+ unsigned char fcr;
+ unsigned char efr;
+ unsigned char dll;
+ unsigned char dlh;
+ unsigned char mdr1;
+ unsigned char scr;
+ unsigned char wer;
+
+ int use_dma;
+ /*
+ * Some bits in registers are cleared on a read, so they must
+ * be saved whenever the register is read, but the bits will not
+ * be immediately processed.
+ */
+ unsigned int lsr_break_flag;
+ unsigned char msr_saved_flags;
+ char name[20];
+ unsigned long port_activity;
+ int context_loss_cnt;
+ u32 errata;
+ u32 features;
+
+ struct gpio_desc *rts_gpiod;
+
+ struct pm_qos_request pm_qos_request;
+ u32 latency;
+ u32 calc_latency;
+ struct work_struct qos_work;
+ bool is_suspending;
+
+ unsigned int rs485_tx_filter_count;
+};
+
+#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
+
+static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
+
+/* Forward declaration of functions */
+static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
+
+static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
+{
+ offset <<= up->port.regshift;
+ return readw(up->port.membase + offset);
+}
+
+static inline void serial_out(struct uart_omap_port *up, int offset, int value)
+{
+ offset <<= up->port.regshift;
+ writew(value, up->port.membase + offset);
+}
+
+static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
+{
+ serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+ serial_out(up, UART_FCR, 0);
+}
+
+#ifdef CONFIG_PM
+static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
+{
+ struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
+
+ if (!pdata || !pdata->get_context_loss_count)
+ return -EINVAL;
+
+ return pdata->get_context_loss_count(up->dev);
+}
+
+/* REVISIT: Remove this when omap3 boots in device tree only mode */
+static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
+{
+ struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
+
+ if (!pdata || !pdata->enable_wakeup)
+ return;
+
+ pdata->enable_wakeup(up->dev, enable);
+}
+#endif /* CONFIG_PM */
+
+/*
+ * Calculate the absolute difference between the desired and actual baud
+ * rate for the given mode.
+ */
+static inline int calculate_baud_abs_diff(struct uart_port *port,
+ unsigned int baud, unsigned int mode)
+{
+ unsigned int n = port->uartclk / (mode * baud);
+ int abs_diff;
+
+ if (n == 0)
+ n = 1;
+
+ abs_diff = baud - (port->uartclk / (mode * n));
+ if (abs_diff < 0)
+ abs_diff = -abs_diff;
+
+ return abs_diff;
+}
+
+/*
+ * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
+ * @port: uart port info
+ * @baud: baudrate for which mode needs to be determined
+ *
+ * Returns true if baud rate is MODE16X and false if MODE13X
+ * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
+ * and Error Rates" determines modes not for all common baud rates.
+ * E.g. for 1000000 baud rate mode must be 16x, but according to that
+ * table it's determined as 13x.
+ */
+static bool
+serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
+{
+ int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
+ int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
+
+ return (abs_diff_13 >= abs_diff_16);
+}
+
+/*
+ * serial_omap_get_divisor - calculate divisor value
+ * @port: uart port info
+ * @baud: baudrate for which divisor needs to be calculated.
+ */
+static unsigned int
+serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
+{
+ unsigned int mode;
+
+ if (!serial_omap_baud_is_mode16(port, baud))
+ mode = 13;
+ else
+ mode = 16;
+ return port->uartclk/(mode * baud);
+}
+
+static void serial_omap_enable_ms(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
+
+ up->ier |= UART_IER_MSI;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static void serial_omap_stop_tx(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ int res;
+
+ /* Handle RS-485 */
+ if (port->rs485.flags & SER_RS485_ENABLED) {
+ if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
+ /* THR interrupt is fired when both TX FIFO and TX
+ * shift register are empty. This means there's nothing
+ * left to transmit now, so make sure the THR interrupt
+ * is fired when TX FIFO is below the trigger level,
+ * disable THR interrupts and toggle the RS-485 GPIO
+ * data direction pin if needed.
+ */
+ up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
+ serial_out(up, UART_OMAP_SCR, up->scr);
+ res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
+ 1 : 0;
+ if (gpiod_get_value(up->rts_gpiod) != res) {
+ if (port->rs485.delay_rts_after_send > 0)
+ mdelay(
+ port->rs485.delay_rts_after_send);
+ gpiod_set_value(up->rts_gpiod, res);
+ }
+ } else {
+ /* We're asked to stop, but there's still stuff in the
+ * UART FIFO, so make sure the THR interrupt is fired
+ * when both TX FIFO and TX shift register are empty.
+ * The next THR interrupt (if no transmission is started
+ * in the meantime) will indicate the end of a
+ * transmission. Therefore we _don't_ disable THR
+ * interrupts in this situation.
+ */
+ up->scr |= OMAP_UART_SCR_TX_EMPTY;
+ serial_out(up, UART_OMAP_SCR, up->scr);
+ return;
+ }
+ }
+
+ if (up->ier & UART_IER_THRI) {
+ up->ier &= ~UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+}
+
+static void serial_omap_stop_rx(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+ up->port.read_status_mask &= ~UART_LSR_DR;
+ serial_out(up, UART_IER, up->ier);
+}
+
+static void serial_omap_put_char(struct uart_omap_port *up, unsigned char ch)
+{
+ serial_out(up, UART_TX, ch);
+
+ if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
+ !(up->port.rs485.flags & SER_RS485_RX_DURING_TX))
+ up->rs485_tx_filter_count++;
+}
+
+static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
+{
+ struct circ_buf *xmit = &up->port.state->xmit;
+ int count;
+
+ if (up->port.x_char) {
+ serial_omap_put_char(up, up->port.x_char);
+ up->port.icount.tx++;
+ up->port.x_char = 0;
+ return;
+ }
+ if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+ serial_omap_stop_tx(&up->port);
+ return;
+ }
+ count = up->port.fifosize / 4;
+ do {
+ serial_omap_put_char(up, xmit->buf[xmit->tail]);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ up->port.icount.tx++;
+
+ if (uart_circ_empty(xmit))
+ break;
+ } while (--count > 0);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&up->port);
+
+ if (uart_circ_empty(xmit))
+ serial_omap_stop_tx(&up->port);
+}
+
+static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
+{
+ if (!(up->ier & UART_IER_THRI)) {
+ up->ier |= UART_IER_THRI;
+ serial_out(up, UART_IER, up->ier);
+ }
+}
+
+static void serial_omap_start_tx(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ int res;
+
+ /* Handle RS-485 */
+ if (port->rs485.flags & SER_RS485_ENABLED) {
+ /* Fire THR interrupts when FIFO is below trigger level */
+ up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
+ serial_out(up, UART_OMAP_SCR, up->scr);
+
+ /* if rts not already enabled */
+ res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
+ if (gpiod_get_value(up->rts_gpiod) != res) {
+ gpiod_set_value(up->rts_gpiod, res);
+ if (port->rs485.delay_rts_before_send > 0)
+ mdelay(port->rs485.delay_rts_before_send);
+ }
+ }
+
+ if ((port->rs485.flags & SER_RS485_ENABLED) &&
+ !(port->rs485.flags & SER_RS485_RX_DURING_TX))
+ up->rs485_tx_filter_count = 0;
+
+ serial_omap_enable_ier_thri(up);
+}
+
+static void serial_omap_throttle(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
+ serial_out(up, UART_IER, up->ier);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static void serial_omap_unthrottle(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ up->ier |= UART_IER_RLSI | UART_IER_RDI;
+ serial_out(up, UART_IER, up->ier);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static unsigned int check_modem_status(struct uart_omap_port *up)
+{
+ unsigned int status;
+
+ status = serial_in(up, UART_MSR);
+ status |= up->msr_saved_flags;
+ up->msr_saved_flags = 0;
+ if ((status & UART_MSR_ANY_DELTA) == 0)
+ return status;
+
+ if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
+ up->port.state != NULL) {
+ if (status & UART_MSR_TERI)
+ up->port.icount.rng++;
+ if (status & UART_MSR_DDSR)
+ up->port.icount.dsr++;
+ if (status & UART_MSR_DDCD)
+ uart_handle_dcd_change
+ (&up->port, status & UART_MSR_DCD);
+ if (status & UART_MSR_DCTS)
+ uart_handle_cts_change
+ (&up->port, status & UART_MSR_CTS);
+ wake_up_interruptible(&up->port.state->port.delta_msr_wait);
+ }
+
+ return status;
+}
+
+static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
+{
+ unsigned int flag;
+
+ /*
+ * Read one data character out to avoid stalling the receiver according
+ * to the table 23-246 of the omap4 TRM.
+ */
+ if (likely(lsr & UART_LSR_DR)) {
+ serial_in(up, UART_RX);
+ if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
+ !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
+ up->rs485_tx_filter_count)
+ up->rs485_tx_filter_count--;
+ }
+
+ up->port.icount.rx++;
+ flag = TTY_NORMAL;
+
+ if (lsr & UART_LSR_BI) {
+ flag = TTY_BREAK;
+ lsr &= ~(UART_LSR_FE | UART_LSR_PE);
+ up->port.icount.brk++;
+ /*
+ * We do the SysRQ and SAK checking
+ * here because otherwise the break
+ * may get masked by ignore_status_mask
+ * or read_status_mask.
+ */
+ if (uart_handle_break(&up->port))
+ return;
+
+ }
+
+ if (lsr & UART_LSR_PE) {
+ flag = TTY_PARITY;
+ up->port.icount.parity++;
+ }
+
+ if (lsr & UART_LSR_FE) {
+ flag = TTY_FRAME;
+ up->port.icount.frame++;
+ }
+
+ if (lsr & UART_LSR_OE)
+ up->port.icount.overrun++;
+
+#ifdef CONFIG_SERIAL_OMAP_CONSOLE
+ if (up->port.line == up->port.cons->index) {
+ /* Recover the break flag from console xmit */
+ lsr |= up->lsr_break_flag;
+ }
+#endif
+ uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
+}
+
+static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
+{
+ unsigned char ch = 0;
+ unsigned int flag;
+
+ if (!(lsr & UART_LSR_DR))
+ return;
+
+ ch = serial_in(up, UART_RX);
+ if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
+ !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
+ up->rs485_tx_filter_count) {
+ up->rs485_tx_filter_count--;
+ return;
+ }
+
+ flag = TTY_NORMAL;
+ up->port.icount.rx++;
+
+ if (uart_handle_sysrq_char(&up->port, ch))
+ return;
+
+ uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
+}
+
+/**
+ * serial_omap_irq() - This handles the interrupt from one port
+ * @irq: uart port irq number
+ * @dev_id: uart port info
+ */
+static irqreturn_t serial_omap_irq(int irq, void *dev_id)
+{
+ struct uart_omap_port *up = dev_id;
+ unsigned int iir, lsr;
+ unsigned int type;
+ irqreturn_t ret = IRQ_NONE;
+ int max_count = 256;
+
+ spin_lock(&up->port.lock);
+
+ do {
+ iir = serial_in(up, UART_IIR);
+ if (iir & UART_IIR_NO_INT)
+ break;
+
+ ret = IRQ_HANDLED;
+ lsr = serial_in(up, UART_LSR);
+
+ /* extract IRQ type from IIR register */
+ type = iir & 0x3e;
+
+ switch (type) {
+ case UART_IIR_MSI:
+ check_modem_status(up);
+ break;
+ case UART_IIR_THRI:
+ transmit_chars(up, lsr);
+ break;
+ case UART_IIR_RX_TIMEOUT:
+ case UART_IIR_RDI:
+ serial_omap_rdi(up, lsr);
+ break;
+ case UART_IIR_RLSI:
+ serial_omap_rlsi(up, lsr);
+ break;
+ case UART_IIR_CTS_RTS_DSR:
+ /* simply try again */
+ break;
+ case UART_IIR_XOFF:
+ default:
+ break;
+ }
+ } while (max_count--);
+
+ spin_unlock(&up->port.lock);
+
+ tty_flip_buffer_push(&up->port.state->port);
+
+ up->port_activity = jiffies;
+
+ return ret;
+}
+
+static unsigned int serial_omap_tx_empty(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+ unsigned int ret = 0;
+
+ dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
+ spin_lock_irqsave(&up->port.lock, flags);
+ ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ return ret;
+}
+
+static unsigned int serial_omap_get_mctrl(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned int status;
+ unsigned int ret = 0;
+
+ status = check_modem_status(up);
+
+ dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
+
+ if (status & UART_MSR_DCD)
+ ret |= TIOCM_CAR;
+ if (status & UART_MSR_RI)
+ ret |= TIOCM_RNG;
+ if (status & UART_MSR_DSR)
+ ret |= TIOCM_DSR;
+ if (status & UART_MSR_CTS)
+ ret |= TIOCM_CTS;
+ return ret;
+}
+
+static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned char mcr = 0, old_mcr, lcr;
+
+ dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
+ if (mctrl & TIOCM_RTS)
+ mcr |= UART_MCR_RTS;
+ if (mctrl & TIOCM_DTR)
+ mcr |= UART_MCR_DTR;
+ if (mctrl & TIOCM_OUT1)
+ mcr |= UART_MCR_OUT1;
+ if (mctrl & TIOCM_OUT2)
+ mcr |= UART_MCR_OUT2;
+ if (mctrl & TIOCM_LOOP)
+ mcr |= UART_MCR_LOOP;
+
+ old_mcr = serial_in(up, UART_MCR);
+ old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
+ UART_MCR_DTR | UART_MCR_RTS);
+ up->mcr = old_mcr | mcr;
+ serial_out(up, UART_MCR, up->mcr);
+
+ /* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
+ lcr = serial_in(up, UART_LCR);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
+ up->efr |= UART_EFR_RTS;
+ else
+ up->efr &= ~UART_EFR_RTS;
+ serial_out(up, UART_EFR, up->efr);
+ serial_out(up, UART_LCR, lcr);
+}
+
+static void serial_omap_break_ctl(struct uart_port *port, int break_state)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+
+ dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
+ spin_lock_irqsave(&up->port.lock, flags);
+ if (break_state == -1)
+ up->lcr |= UART_LCR_SBC;
+ else
+ up->lcr &= ~UART_LCR_SBC;
+ serial_out(up, UART_LCR, up->lcr);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static int serial_omap_startup(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+ int retval;
+
+ /*
+ * Allocate the IRQ
+ */
+ retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
+ up->name, up);
+ if (retval)
+ return retval;
+
+ /* Optional wake-up IRQ */
+ if (up->wakeirq) {
+ retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
+ if (retval) {
+ free_irq(up->port.irq, up);
+ return retval;
+ }
+ }
+
+ dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
+
+ pm_runtime_get_sync(up->dev);
+ /*
+ * Clear the FIFO buffers and disable them.
+ * (they will be reenabled in set_termios())
+ */
+ serial_omap_clear_fifos(up);
+
+ /*
+ * Clear the interrupt registers.
+ */
+ (void) serial_in(up, UART_LSR);
+ if (serial_in(up, UART_LSR) & UART_LSR_DR)
+ (void) serial_in(up, UART_RX);
+ (void) serial_in(up, UART_IIR);
+ (void) serial_in(up, UART_MSR);
+
+ /*
+ * Now, initialize the UART
+ */
+ serial_out(up, UART_LCR, UART_LCR_WLEN8);
+ spin_lock_irqsave(&up->port.lock, flags);
+ /*
+ * Most PC uarts need OUT2 raised to enable interrupts.
+ */
+ up->port.mctrl |= TIOCM_OUT2;
+ serial_omap_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ up->msr_saved_flags = 0;
+ /*
+ * Finally, enable interrupts. Note: Modem status interrupts
+ * are set via set_termios(), which will be occurring imminently
+ * anyway, so we don't enable them here.
+ */
+ up->ier = UART_IER_RLSI | UART_IER_RDI;
+ serial_out(up, UART_IER, up->ier);
+
+ /* Enable module level wake up */
+ up->wer = OMAP_UART_WER_MOD_WKUP;
+ if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
+ up->wer |= OMAP_UART_TX_WAKEUP_EN;
+
+ serial_out(up, UART_OMAP_WER, up->wer);
+
+ up->port_activity = jiffies;
+ return 0;
+}
+
+static void serial_omap_shutdown(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned long flags;
+
+ dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
+
+ /*
+ * Disable interrupts from this port
+ */
+ up->ier = 0;
+ serial_out(up, UART_IER, 0);
+
+ spin_lock_irqsave(&up->port.lock, flags);
+ up->port.mctrl &= ~TIOCM_OUT2;
+ serial_omap_set_mctrl(&up->port, up->port.mctrl);
+ spin_unlock_irqrestore(&up->port.lock, flags);
+
+ /*
+ * Disable break condition and FIFOs
+ */
+ serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
+ serial_omap_clear_fifos(up);
+
+ /*
+ * Read data port to reset things, and then free the irq
+ */
+ if (serial_in(up, UART_LSR) & UART_LSR_DR)
+ (void) serial_in(up, UART_RX);
+
+ pm_runtime_put_sync(up->dev);
+ free_irq(up->port.irq, up);
+ dev_pm_clear_wake_irq(up->dev);
+}
+
+static void serial_omap_uart_qos_work(struct work_struct *work)
+{
+ struct uart_omap_port *up = container_of(work, struct uart_omap_port,
+ qos_work);
+
+ cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
+}
+
+static void
+serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
+ const struct ktermios *old)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned char cval = 0;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
+
+ if (termios->c_cflag & CSTOPB)
+ cval |= UART_LCR_STOP;
+ if (termios->c_cflag & PARENB)
+ cval |= UART_LCR_PARITY;
+ if (!(termios->c_cflag & PARODD))
+ cval |= UART_LCR_EPAR;
+ if (termios->c_cflag & CMSPAR)
+ cval |= UART_LCR_SPAR;
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
+ quot = serial_omap_get_divisor(port, baud);
+
+ /* calculate wakeup latency constraint */
+ up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
+ up->latency = up->calc_latency;
+ schedule_work(&up->qos_work);
+
+ up->dll = quot & 0xff;
+ up->dlh = quot >> 8;
+ up->mdr1 = UART_OMAP_MDR1_DISABLE;
+
+ up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
+ UART_FCR_ENABLE_FIFO;
+
+ /*
+ * Ok, we're now changing the port state. Do it with
+ * interrupts disabled.
+ */
+ spin_lock_irqsave(&up->port.lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
+ if (termios->c_iflag & INPCK)
+ up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ up->port.read_status_mask |= UART_LSR_BI;
+
+ /*
+ * Characters to ignore
+ */
+ up->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
+ if (termios->c_iflag & IGNBRK) {
+ up->port.ignore_status_mask |= UART_LSR_BI;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ up->port.ignore_status_mask |= UART_LSR_OE;
+ }
+
+ /*
+ * ignore all characters if CREAD is not set
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ up->port.ignore_status_mask |= UART_LSR_DR;
+
+ /*
+ * Modem status interrupts
+ */
+ up->ier &= ~UART_IER_MSI;
+ if (UART_ENABLE_MS(&up->port, termios->c_cflag))
+ up->ier |= UART_IER_MSI;
+ serial_out(up, UART_IER, up->ier);
+ serial_out(up, UART_LCR, cval); /* reset DLAB */
+ up->lcr = cval;
+ up->scr = 0;
+
+ /* FIFOs and DMA Settings */
+
+ /* FCR can be changed only when the
+ * baud clock is not running
+ * DLL_REG and DLH_REG set to 0.
+ */
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+ serial_out(up, UART_DLL, 0);
+ serial_out(up, UART_DLM, 0);
+ serial_out(up, UART_LCR, 0);
+
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+ up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
+ up->efr &= ~UART_EFR_SCD;
+ serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
+
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+ up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
+ serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
+ /* FIFO ENABLE, DMA MODE */
+
+ up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
+ /*
+ * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
+ * sets Enables the granularity of 1 for TRIGGER RX
+ * level. Along with setting RX FIFO trigger level
+ * to 1 (as noted below, 16 characters) and TLR[3:0]
+ * to zero this will result RX FIFO threshold level
+ * to 1 character, instead of 16 as noted in comment
+ * below.
+ */
+
+ /* Set receive FIFO threshold to 16 characters and
+ * transmit FIFO threshold to 32 spaces
+ */
+ up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
+ up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
+ up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
+ UART_FCR_ENABLE_FIFO;
+
+ serial_out(up, UART_FCR, up->fcr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+ serial_out(up, UART_OMAP_SCR, up->scr);
+
+ /* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+ serial_out(up, UART_MCR, up->mcr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(up, UART_EFR, up->efr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+
+ /* Protocol, Baud Rate, and Interrupt Settings */
+
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
+
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
+
+ serial_out(up, UART_LCR, 0);
+ serial_out(up, UART_IER, 0);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+ serial_out(up, UART_DLL, up->dll); /* LS of divisor */
+ serial_out(up, UART_DLM, up->dlh); /* MS of divisor */
+
+ serial_out(up, UART_LCR, 0);
+ serial_out(up, UART_IER, up->ier);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+ serial_out(up, UART_EFR, up->efr);
+ serial_out(up, UART_LCR, cval);
+
+ if (!serial_omap_baud_is_mode16(port, baud))
+ up->mdr1 = UART_OMAP_MDR1_13X_MODE;
+ else
+ up->mdr1 = UART_OMAP_MDR1_16X_MODE;
+
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
+
+ /* Configure flow control */
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+
+ /* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
+ serial_out(up, UART_XON1, termios->c_cc[VSTART]);
+ serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
+
+ /* Enable access to TCR/TLR */
+ serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+ serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
+
+ serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
+
+ up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
+
+ if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
+ /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
+ up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
+ up->efr |= UART_EFR_CTS;
+ } else {
+ /* Disable AUTORTS and AUTOCTS */
+ up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
+ }
+
+ if (up->port.flags & UPF_SOFT_FLOW) {
+ /* clear SW control mode bits */
+ up->efr &= OMAP_UART_SW_CLR;
+
+ /*
+ * IXON Flag:
+ * Enable XON/XOFF flow control on input.
+ * Receiver compares XON1, XOFF1.
+ */
+ if (termios->c_iflag & IXON)
+ up->efr |= OMAP_UART_SW_RX;
+
+ /*
+ * IXOFF Flag:
+ * Enable XON/XOFF flow control on output.
+ * Transmit XON1, XOFF1
+ */
+ if (termios->c_iflag & IXOFF) {
+ up->port.status |= UPSTAT_AUTOXOFF;
+ up->efr |= OMAP_UART_SW_TX;
+ }
+
+ /*
+ * IXANY Flag:
+ * Enable any character to restart output.
+ * Operation resumes after receiving any
+ * character after recognition of the XOFF character
+ */
+ if (termios->c_iflag & IXANY)
+ up->mcr |= UART_MCR_XONANY;
+ else
+ up->mcr &= ~UART_MCR_XONANY;
+ }
+ serial_out(up, UART_MCR, up->mcr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(up, UART_EFR, up->efr);
+ serial_out(up, UART_LCR, up->lcr);
+
+ serial_omap_set_mctrl(&up->port, up->port.mctrl);
+
+ spin_unlock_irqrestore(&up->port.lock, flags);
+ dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
+}
+
+static void
+serial_omap_pm(struct uart_port *port, unsigned int state,
+ unsigned int oldstate)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned char efr;
+
+ dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
+
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ efr = serial_in(up, UART_EFR);
+ serial_out(up, UART_EFR, efr | UART_EFR_ECB);
+ serial_out(up, UART_LCR, 0);
+
+ serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
+ serial_out(up, UART_EFR, efr);
+ serial_out(up, UART_LCR, 0);
+}
+
+static void serial_omap_release_port(struct uart_port *port)
+{
+ dev_dbg(port->dev, "serial_omap_release_port+\n");
+}
+
+static int serial_omap_request_port(struct uart_port *port)
+{
+ dev_dbg(port->dev, "serial_omap_request_port+\n");
+ return 0;
+}
+
+static void serial_omap_config_port(struct uart_port *port, int flags)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
+ up->port.line);
+ up->port.type = PORT_OMAP;
+ up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
+}
+
+static int
+serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ /* we don't want the core code to modify any port params */
+ dev_dbg(port->dev, "serial_omap_verify_port+\n");
+ return -EINVAL;
+}
+
+static const char *
+serial_omap_type(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
+ return up->name;
+}
+
+static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
+{
+ unsigned int status, tmout = 10000;
+
+ /* Wait up to 10ms for the character(s) to be sent. */
+ do {
+ status = serial_in(up, UART_LSR);
+
+ if (status & UART_LSR_BI)
+ up->lsr_break_flag = UART_LSR_BI;
+
+ if (--tmout == 0)
+ break;
+ udelay(1);
+ } while (!uart_lsr_tx_empty(status));
+
+ /* Wait up to 1s for flow control if necessary */
+ if (up->port.flags & UPF_CONS_FLOW) {
+ tmout = 1000000;
+ for (tmout = 1000000; tmout; tmout--) {
+ unsigned int msr = serial_in(up, UART_MSR);
+
+ up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
+ if (msr & UART_MSR_CTS)
+ break;
+
+ udelay(1);
+ }
+ }
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+
+static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ wait_for_xmitr(up);
+ serial_out(up, UART_TX, ch);
+}
+
+static int serial_omap_poll_get_char(struct uart_port *port)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned int status;
+
+ status = serial_in(up, UART_LSR);
+ if (!(status & UART_LSR_DR)) {
+ status = NO_POLL_CHAR;
+ goto out;
+ }
+
+ status = serial_in(up, UART_RX);
+
+out:
+ return status;
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
+#ifdef CONFIG_SERIAL_OMAP_CONSOLE
+
+#ifdef CONFIG_SERIAL_EARLYCON
+static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
+{
+ offset <<= port->regshift;
+ return readw(port->membase + offset);
+}
+
+static void omap_serial_early_out(struct uart_port *port, int offset,
+ int value)
+{
+ offset <<= port->regshift;
+ writew(value, port->membase + offset);
+}
+
+static void omap_serial_early_putc(struct uart_port *port, unsigned char c)
+{
+ unsigned int status;
+
+ for (;;) {
+ status = omap_serial_early_in(port, UART_LSR);
+ if (uart_lsr_tx_empty(status))
+ break;
+ cpu_relax();
+ }
+ omap_serial_early_out(port, UART_TX, c);
+}
+
+static void early_omap_serial_write(struct console *console, const char *s,
+ unsigned int count)
+{
+ struct earlycon_device *device = console->data;
+ struct uart_port *port = &device->port;
+
+ uart_console_write(port, s, count, omap_serial_early_putc);
+}
+
+static int __init early_omap_serial_setup(struct earlycon_device *device,
+ const char *options)
+{
+ struct uart_port *port = &device->port;
+
+ if (!(device->port.membase || device->port.iobase))
+ return -ENODEV;
+
+ port->regshift = 2;
+ device->con->write = early_omap_serial_write;
+ return 0;
+}
+
+OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
+OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
+OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
+#endif /* CONFIG_SERIAL_EARLYCON */
+
+static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
+
+static struct uart_driver serial_omap_reg;
+
+static void serial_omap_console_putchar(struct uart_port *port, unsigned char ch)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+
+ wait_for_xmitr(up);
+ serial_out(up, UART_TX, ch);
+}
+
+static void
+serial_omap_console_write(struct console *co, const char *s,
+ unsigned int count)
+{
+ struct uart_omap_port *up = serial_omap_console_ports[co->index];
+ unsigned long flags;
+ unsigned int ier;
+ int locked = 1;
+
+ local_irq_save(flags);
+ if (up->port.sysrq)
+ locked = 0;
+ else if (oops_in_progress)
+ locked = spin_trylock(&up->port.lock);
+ else
+ spin_lock(&up->port.lock);
+
+ /*
+ * First save the IER then disable the interrupts
+ */
+ ier = serial_in(up, UART_IER);
+ serial_out(up, UART_IER, 0);
+
+ uart_console_write(&up->port, s, count, serial_omap_console_putchar);
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ wait_for_xmitr(up);
+ serial_out(up, UART_IER, ier);
+ /*
+ * The receive handling will happen properly because the
+ * receive ready bit will still be set; it is not cleared
+ * on read. However, modem control will not, we must
+ * call it if we have saved something in the saved flags
+ * while processing with interrupts off.
+ */
+ if (up->msr_saved_flags)
+ check_modem_status(up);
+
+ if (locked)
+ spin_unlock(&up->port.lock);
+ local_irq_restore(flags);
+}
+
+static int __init
+serial_omap_console_setup(struct console *co, char *options)
+{
+ struct uart_omap_port *up;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ if (serial_omap_console_ports[co->index] == NULL)
+ return -ENODEV;
+ up = serial_omap_console_ports[co->index];
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+ return uart_set_options(&up->port, co, baud, parity, bits, flow);
+}
+
+static struct console serial_omap_console = {
+ .name = OMAP_SERIAL_NAME,
+ .write = serial_omap_console_write,
+ .device = uart_console_device,
+ .setup = serial_omap_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &serial_omap_reg,
+};
+
+static void serial_omap_add_console_port(struct uart_omap_port *up)
+{
+ serial_omap_console_ports[up->port.line] = up;
+}
+
+#define OMAP_CONSOLE (&serial_omap_console)
+
+#else
+
+#define OMAP_CONSOLE NULL
+
+static inline void serial_omap_add_console_port(struct uart_omap_port *up)
+{}
+
+#endif
+
+/* Enable or disable the rs485 support */
+static int
+serial_omap_config_rs485(struct uart_port *port, struct ktermios *termios,
+ struct serial_rs485 *rs485)
+{
+ struct uart_omap_port *up = to_uart_omap_port(port);
+ unsigned int mode;
+ int val;
+
+ /* Disable interrupts from this port */
+ mode = up->ier;
+ up->ier = 0;
+ serial_out(up, UART_IER, 0);
+
+ /* enable / disable rts */
+ val = (rs485->flags & SER_RS485_ENABLED) ?
+ SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
+ val = (rs485->flags & val) ? 1 : 0;
+ gpiod_set_value(up->rts_gpiod, val);
+
+ /* Enable interrupts */
+ up->ier = mode;
+ serial_out(up, UART_IER, up->ier);
+
+ /* If RS-485 is disabled, make sure the THR interrupt is fired when
+ * TX FIFO is below the trigger level.
+ */
+ if (!(rs485->flags & SER_RS485_ENABLED) &&
+ (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
+ up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
+ serial_out(up, UART_OMAP_SCR, up->scr);
+ }
+
+ return 0;
+}
+
+static const struct uart_ops serial_omap_pops = {
+ .tx_empty = serial_omap_tx_empty,
+ .set_mctrl = serial_omap_set_mctrl,
+ .get_mctrl = serial_omap_get_mctrl,
+ .stop_tx = serial_omap_stop_tx,
+ .start_tx = serial_omap_start_tx,
+ .throttle = serial_omap_throttle,
+ .unthrottle = serial_omap_unthrottle,
+ .stop_rx = serial_omap_stop_rx,
+ .enable_ms = serial_omap_enable_ms,
+ .break_ctl = serial_omap_break_ctl,
+ .startup = serial_omap_startup,
+ .shutdown = serial_omap_shutdown,
+ .set_termios = serial_omap_set_termios,
+ .pm = serial_omap_pm,
+ .type = serial_omap_type,
+ .release_port = serial_omap_release_port,
+ .request_port = serial_omap_request_port,
+ .config_port = serial_omap_config_port,
+ .verify_port = serial_omap_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_put_char = serial_omap_poll_put_char,
+ .poll_get_char = serial_omap_poll_get_char,
+#endif
+};
+
+static struct uart_driver serial_omap_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "OMAP-SERIAL",
+ .dev_name = OMAP_SERIAL_NAME,
+ .nr = OMAP_MAX_HSUART_PORTS,
+ .cons = OMAP_CONSOLE,
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int serial_omap_prepare(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ up->is_suspending = true;
+
+ return 0;
+}
+
+static void serial_omap_complete(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ up->is_suspending = false;
+}
+
+static int serial_omap_suspend(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ uart_suspend_port(&serial_omap_reg, &up->port);
+ flush_work(&up->qos_work);
+
+ if (device_may_wakeup(dev))
+ serial_omap_enable_wakeup(up, true);
+ else
+ serial_omap_enable_wakeup(up, false);
+
+ return 0;
+}
+
+static int serial_omap_resume(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ serial_omap_enable_wakeup(up, false);
+
+ uart_resume_port(&serial_omap_reg, &up->port);
+
+ return 0;
+}
+#else
+#define serial_omap_prepare NULL
+#define serial_omap_complete NULL
+#endif /* CONFIG_PM_SLEEP */
+
+static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
+{
+ u32 mvr, scheme;
+ u16 revision, major, minor;
+
+ mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
+
+ /* Check revision register scheme */
+ scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
+
+ switch (scheme) {
+ case 0: /* Legacy Scheme: OMAP2/3 */
+ /* MINOR_REV[0:4], MAJOR_REV[4:7] */
+ major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
+ OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
+ minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
+ break;
+ case 1:
+ /* New Scheme: OMAP4+ */
+ /* MINOR_REV[0:5], MAJOR_REV[8:10] */
+ major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
+ OMAP_UART_MVR_MAJ_SHIFT;
+ minor = (mvr & OMAP_UART_MVR_MIN_MASK);
+ break;
+ default:
+ dev_warn(up->dev,
+ "Unknown %s revision, defaulting to highest\n",
+ up->name);
+ /* highest possible revision */
+ major = 0xff;
+ minor = 0xff;
+ }
+
+ /* normalize revision for the driver */
+ revision = UART_BUILD_REVISION(major, minor);
+
+ switch (revision) {
+ case OMAP_UART_REV_46:
+ up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
+ UART_ERRATA_i291_DMA_FORCEIDLE);
+ break;
+ case OMAP_UART_REV_52:
+ up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
+ UART_ERRATA_i291_DMA_FORCEIDLE);
+ up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
+ break;
+ case OMAP_UART_REV_63:
+ up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
+ up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
+ break;
+ default:
+ break;
+ }
+}
+
+static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
+{
+ struct omap_uart_port_info *omap_up_info;
+
+ omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
+ if (!omap_up_info)
+ return NULL; /* out of memory */
+
+ of_property_read_u32(dev->of_node, "clock-frequency",
+ &omap_up_info->uartclk);
+
+ omap_up_info->flags = UPF_BOOT_AUTOCONF;
+
+ return omap_up_info;
+}
+
+static const struct serial_rs485 serial_omap_rs485_supported = {
+ .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND |
+ SER_RS485_RX_DURING_TX,
+ .delay_rts_before_send = 1,
+ .delay_rts_after_send = 1,
+};
+
+static int serial_omap_probe_rs485(struct uart_omap_port *up,
+ struct device *dev)
+{
+ struct serial_rs485 *rs485conf = &up->port.rs485;
+ struct device_node *np = dev->of_node;
+ enum gpiod_flags gflags;
+ int ret;
+
+ rs485conf->flags = 0;
+ up->rts_gpiod = NULL;
+
+ if (!np)
+ return 0;
+
+ up->port.rs485_config = serial_omap_config_rs485;
+ up->port.rs485_supported = serial_omap_rs485_supported;
+
+ ret = uart_get_rs485_mode(&up->port);
+ if (ret)
+ return ret;
+
+ if (of_property_read_bool(np, "rs485-rts-active-high")) {
+ rs485conf->flags |= SER_RS485_RTS_ON_SEND;
+ rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
+ } else {
+ rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
+ rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
+ }
+
+ /* check for tx enable gpio */
+ gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
+ GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+ up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
+ if (IS_ERR(up->rts_gpiod)) {
+ ret = PTR_ERR(up->rts_gpiod);
+ if (ret == -EPROBE_DEFER)
+ return ret;
+
+ up->rts_gpiod = NULL;
+ up->port.rs485_supported = (const struct serial_rs485) { };
+ if (rs485conf->flags & SER_RS485_ENABLED) {
+ dev_err(dev, "disabling RS-485 (rts-gpio missing in device tree)\n");
+ memset(rs485conf, 0, sizeof(*rs485conf));
+ }
+ } else {
+ gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
+ }
+
+ return 0;
+}
+
+static int serial_omap_probe(struct platform_device *pdev)
+{
+ struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
+ struct uart_omap_port *up;
+ struct resource *mem;
+ void __iomem *base;
+ int uartirq = 0;
+ int wakeirq = 0;
+ int ret;
+
+ /* The optional wakeirq may be specified in the board dts file */
+ if (pdev->dev.of_node) {
+ uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+ if (!uartirq)
+ return -EPROBE_DEFER;
+ wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
+ omap_up_info = of_get_uart_port_info(&pdev->dev);
+ pdev->dev.platform_data = omap_up_info;
+ } else {
+ uartirq = platform_get_irq(pdev, 0);
+ if (uartirq < 0)
+ return -EPROBE_DEFER;
+ }
+
+ up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
+ if (!up)
+ return -ENOMEM;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ up->dev = &pdev->dev;
+ up->port.dev = &pdev->dev;
+ up->port.type = PORT_OMAP;
+ up->port.iotype = UPIO_MEM;
+ up->port.irq = uartirq;
+ up->port.regshift = 2;
+ up->port.fifosize = 64;
+ up->port.ops = &serial_omap_pops;
+ up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
+
+ if (pdev->dev.of_node)
+ ret = of_alias_get_id(pdev->dev.of_node, "serial");
+ else
+ ret = pdev->id;
+
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
+ ret);
+ goto err_port_line;
+ }
+ up->port.line = ret;
+
+ if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
+ dev_err(&pdev->dev, "uart ID %d > MAX %d.\n", up->port.line,
+ OMAP_MAX_HSUART_PORTS);
+ ret = -ENXIO;
+ goto err_port_line;
+ }
+
+ up->wakeirq = wakeirq;
+ if (!up->wakeirq)
+ dev_info(up->port.dev, "no wakeirq for uart%d\n",
+ up->port.line);
+
+ sprintf(up->name, "OMAP UART%d", up->port.line);
+ up->port.mapbase = mem->start;
+ up->port.membase = base;
+ up->port.flags = omap_up_info->flags;
+ up->port.uartclk = omap_up_info->uartclk;
+ if (!up->port.uartclk) {
+ up->port.uartclk = DEFAULT_CLK_SPEED;
+ dev_warn(&pdev->dev,
+ "No clock speed specified: using default: %d\n",
+ DEFAULT_CLK_SPEED);
+ }
+
+ ret = serial_omap_probe_rs485(up, &pdev->dev);
+ if (ret < 0)
+ goto err_rs485;
+
+ up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
+ up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
+ cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
+ INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
+
+ platform_set_drvdata(pdev, up);
+ if (omap_up_info->autosuspend_timeout == 0)
+ omap_up_info->autosuspend_timeout = -1;
+
+ device_init_wakeup(up->dev, true);
+
+ pm_runtime_enable(&pdev->dev);
+
+ pm_runtime_get_sync(&pdev->dev);
+
+ omap_serial_fill_features_erratas(up);
+
+ ui[up->port.line] = up;
+ serial_omap_add_console_port(up);
+
+ ret = uart_add_one_port(&serial_omap_reg, &up->port);
+ if (ret != 0)
+ goto err_add_port;
+
+ return 0;
+
+err_add_port:
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ cpu_latency_qos_remove_request(&up->pm_qos_request);
+ device_init_wakeup(up->dev, false);
+err_rs485:
+err_port_line:
+ return ret;
+}
+
+static int serial_omap_remove(struct platform_device *dev)
+{
+ struct uart_omap_port *up = platform_get_drvdata(dev);
+
+ pm_runtime_get_sync(up->dev);
+
+ uart_remove_one_port(&serial_omap_reg, &up->port);
+
+ pm_runtime_put_sync(up->dev);
+ pm_runtime_disable(up->dev);
+ cpu_latency_qos_remove_request(&up->pm_qos_request);
+ device_init_wakeup(&dev->dev, false);
+
+ return 0;
+}
+
+/*
+ * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
+ * The access to uart register after MDR1 Access
+ * causes UART to corrupt data.
+ *
+ * Need a delay =
+ * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
+ * give 10 times as much
+ */
+static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
+{
+ u8 timeout = 255;
+
+ serial_out(up, UART_OMAP_MDR1, mdr1);
+ udelay(2);
+ serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
+ UART_FCR_CLEAR_RCVR);
+ /*
+ * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
+ * TX_FIFO_E bit is 1.
+ */
+ while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
+ (UART_LSR_THRE | UART_LSR_DR))) {
+ timeout--;
+ if (!timeout) {
+ /* Should *never* happen. we warn and carry on */
+ dev_crit(up->dev, "Errata i202: timedout %x\n",
+ serial_in(up, UART_LSR));
+ break;
+ }
+ udelay(1);
+ }
+}
+
+#ifdef CONFIG_PM
+static void serial_omap_restore_context(struct uart_omap_port *up)
+{
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
+ else
+ serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
+
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
+ serial_out(up, UART_EFR, UART_EFR_ECB);
+ serial_out(up, UART_LCR, 0x0); /* Operational mode */
+ serial_out(up, UART_IER, 0x0);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
+ serial_out(up, UART_DLL, up->dll);
+ serial_out(up, UART_DLM, up->dlh);
+ serial_out(up, UART_LCR, 0x0); /* Operational mode */
+ serial_out(up, UART_IER, up->ier);
+ serial_out(up, UART_FCR, up->fcr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
+ serial_out(up, UART_MCR, up->mcr);
+ serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
+ serial_out(up, UART_OMAP_SCR, up->scr);
+ serial_out(up, UART_EFR, up->efr);
+ serial_out(up, UART_LCR, up->lcr);
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
+ serial_out(up, UART_OMAP_WER, up->wer);
+}
+
+static int serial_omap_runtime_suspend(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ if (!up)
+ return -EINVAL;
+
+ /*
+ * When using 'no_console_suspend', the console UART must not be
+ * suspended. Since driver suspend is managed by runtime suspend,
+ * preventing runtime suspend (by returning error) will keep device
+ * active during suspend.
+ */
+ if (up->is_suspending && !console_suspend_enabled &&
+ uart_console(&up->port))
+ return -EBUSY;
+
+ up->context_loss_cnt = serial_omap_get_context_loss_count(up);
+
+ serial_omap_enable_wakeup(up, true);
+
+ up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
+ schedule_work(&up->qos_work);
+
+ return 0;
+}
+
+static int serial_omap_runtime_resume(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ int loss_cnt = serial_omap_get_context_loss_count(up);
+
+ serial_omap_enable_wakeup(up, false);
+
+ if (loss_cnt < 0) {
+ dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
+ loss_cnt);
+ serial_omap_restore_context(up);
+ } else if (up->context_loss_cnt != loss_cnt) {
+ serial_omap_restore_context(up);
+ }
+ up->latency = up->calc_latency;
+ schedule_work(&up->qos_work);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops serial_omap_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
+ SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
+ serial_omap_runtime_resume, NULL)
+ .prepare = serial_omap_prepare,
+ .complete = serial_omap_complete,
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id omap_serial_of_match[] = {
+ { .compatible = "ti,omap2-uart" },
+ { .compatible = "ti,omap3-uart" },
+ { .compatible = "ti,omap4-uart" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, omap_serial_of_match);
+#endif
+
+static struct platform_driver serial_omap_driver = {
+ .probe = serial_omap_probe,
+ .remove = serial_omap_remove,
+ .driver = {
+ .name = OMAP_SERIAL_DRIVER_NAME,
+ .pm = &serial_omap_dev_pm_ops,
+ .of_match_table = of_match_ptr(omap_serial_of_match),
+ },
+};
+
+static int __init serial_omap_init(void)
+{
+ int ret;
+
+ ret = uart_register_driver(&serial_omap_reg);
+ if (ret != 0)
+ return ret;
+ ret = platform_driver_register(&serial_omap_driver);
+ if (ret != 0)
+ uart_unregister_driver(&serial_omap_reg);
+ return ret;
+}
+
+static void __exit serial_omap_exit(void)
+{
+ platform_driver_unregister(&serial_omap_driver);
+ uart_unregister_driver(&serial_omap_reg);
+}
+
+module_init(serial_omap_init);
+module_exit(serial_omap_exit);
+
+MODULE_DESCRIPTION("OMAP High Speed UART driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Texas Instruments Inc");