diff options
Diffstat (limited to 'drivers/tty/serial/etraxfs-uart.c')
| -rw-r--r-- | drivers/tty/serial/etraxfs-uart.c | 960 |
1 files changed, 0 insertions, 960 deletions
diff --git a/drivers/tty/serial/etraxfs-uart.c b/drivers/tty/serial/etraxfs-uart.c deleted file mode 100644 index 24bf6bfb29b4..000000000000 --- a/drivers/tty/serial/etraxfs-uart.c +++ /dev/null @@ -1,960 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include <linux/module.h> -#include <linux/init.h> -#include <linux/console.h> -#include <linux/platform_device.h> -#include <linux/serial_core.h> -#include <linux/tty_flip.h> -#include <linux/of.h> -#include <linux/gpio.h> -#include <linux/of_irq.h> -#include <linux/of_address.h> -#include <hwregs/ser_defs.h> - -#include "serial_mctrl_gpio.h" - -#define DRV_NAME "etraxfs-uart" -#define UART_NR CONFIG_ETRAX_SERIAL_PORTS - -#define MODIFY_REG(instance, reg, var) \ - do { \ - if (REG_RD_INT(ser, instance, reg) != \ - REG_TYPE_CONV(int, reg_ser_##reg, var)) \ - REG_WR(ser, instance, reg, var); \ - } while (0) - -struct uart_cris_port { - struct uart_port port; - - int initialized; - int irq; - - void __iomem *regi_ser; - - struct mctrl_gpios *gpios; - - int write_ongoing; -}; - -static struct uart_driver etraxfs_uart_driver; -static struct uart_port *console_port; -static int console_baud = 115200; -static struct uart_cris_port *etraxfs_uart_ports[UART_NR]; - -static void cris_serial_port_init(struct uart_port *port, int line); -static void etraxfs_uart_stop_rx(struct uart_port *port); -static inline void etraxfs_uart_start_tx_bottom(struct uart_port *port); - -#ifdef CONFIG_SERIAL_ETRAXFS_CONSOLE -static void -cris_console_write(struct console *co, const char *s, unsigned int count) -{ - struct uart_cris_port *up; - int i; - reg_ser_r_stat_din stat; - reg_ser_rw_tr_dma_en tr_dma_en, old; - - up = etraxfs_uart_ports[co->index]; - - if (!up) - return; - - /* Switch to manual mode. */ - tr_dma_en = old = REG_RD(ser, up->regi_ser, rw_tr_dma_en); - if (tr_dma_en.en == regk_ser_yes) { - tr_dma_en.en = regk_ser_no; - REG_WR(ser, up->regi_ser, rw_tr_dma_en, tr_dma_en); - } - - /* Send data. */ - for (i = 0; i < count; i++) { - /* LF -> CRLF */ - if (s[i] == '\n') { - do { - stat = REG_RD(ser, up->regi_ser, r_stat_din); - } while (!stat.tr_rdy); - REG_WR_INT(ser, up->regi_ser, rw_dout, '\r'); - } - /* Wait until transmitter is ready and send. */ - do { - stat = REG_RD(ser, up->regi_ser, r_stat_din); - } while (!stat.tr_rdy); - REG_WR_INT(ser, up->regi_ser, rw_dout, s[i]); - } - - /* Restore mode. */ - if (tr_dma_en.en != old.en) - REG_WR(ser, up->regi_ser, rw_tr_dma_en, old); -} - -static int __init -cris_console_setup(struct console *co, char *options) -{ - struct uart_port *port; - int baud = 115200; - int bits = 8; - int parity = 'n'; - int flow = 'n'; - - if (co->index < 0 || co->index >= UART_NR) - co->index = 0; - port = &etraxfs_uart_ports[co->index]->port; - console_port = port; - - co->flags |= CON_CONSDEV; - - if (options) - uart_parse_options(options, &baud, &parity, &bits, &flow); - console_baud = baud; - cris_serial_port_init(port, co->index); - uart_set_options(port, co, baud, parity, bits, flow); - - return 0; -} - -static struct console cris_console = { - .name = "ttyS", - .write = cris_console_write, - .device = uart_console_device, - .setup = cris_console_setup, - .flags = CON_PRINTBUFFER, - .index = -1, - .data = &etraxfs_uart_driver, -}; -#endif /* CONFIG_SERIAL_ETRAXFS_CONSOLE */ - -static struct uart_driver etraxfs_uart_driver = { - .owner = THIS_MODULE, - .driver_name = "serial", - .dev_name = "ttyS", - .major = TTY_MAJOR, - .minor = 64, - .nr = UART_NR, -#ifdef CONFIG_SERIAL_ETRAXFS_CONSOLE - .cons = &cris_console, -#endif /* CONFIG_SERIAL_ETRAXFS_CONSOLE */ -}; - -static inline int crisv32_serial_get_rts(struct uart_cris_port *up) -{ - void __iomem *regi_ser = up->regi_ser; - /* - * Return what the user has controlled rts to or - * what the pin is? (if auto_rts is used it differs during tx) - */ - reg_ser_r_stat_din rstat = REG_RD(ser, regi_ser, r_stat_din); - - return !(rstat.rts_n == regk_ser_active); -} - -/* - * A set = 0 means 3.3V on the pin, bitvalue: 0=active, 1=inactive - * 0=0V , 1=3.3V - */ -static inline void crisv32_serial_set_rts(struct uart_cris_port *up, - int set, int force) -{ - void __iomem *regi_ser = up->regi_ser; - - unsigned long flags; - reg_ser_rw_rec_ctrl rec_ctrl; - - local_irq_save(flags); - rec_ctrl = REG_RD(ser, regi_ser, rw_rec_ctrl); - - if (set) - rec_ctrl.rts_n = regk_ser_active; - else - rec_ctrl.rts_n = regk_ser_inactive; - REG_WR(ser, regi_ser, rw_rec_ctrl, rec_ctrl); - local_irq_restore(flags); -} - -static inline int crisv32_serial_get_cts(struct uart_cris_port *up) -{ - void __iomem *regi_ser = up->regi_ser; - reg_ser_r_stat_din rstat = REG_RD(ser, regi_ser, r_stat_din); - - return (rstat.cts_n == regk_ser_active); -} - -/* - * Send a single character for XON/XOFF purposes. We do it in this separate - * function instead of the alternative support port.x_char, in the ...start_tx - * function, so we don't mix up this case with possibly enabling transmission - * of queued-up data (in case that's disabled after *receiving* an XOFF or - * negative CTS). This function is used for both DMA and non-DMA case; see HW - * docs specifically blessing sending characters manually when DMA for - * transmission is enabled and running. We may be asked to transmit despite - * the transmitter being disabled by a ..._stop_tx call so we need to enable - * it temporarily but restore the state afterwards. - */ -static void etraxfs_uart_send_xchar(struct uart_port *port, char ch) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - reg_ser_rw_dout dout = { .data = ch }; - reg_ser_rw_ack_intr ack_intr = { .tr_rdy = regk_ser_yes }; - reg_ser_r_stat_din rstat; - reg_ser_rw_tr_ctrl prev_tr_ctrl, tr_ctrl; - void __iomem *regi_ser = up->regi_ser; - unsigned long flags; - - /* - * Wait for tr_rdy in case a character is already being output. Make - * sure we have integrity between the register reads and the writes - * below, but don't busy-wait with interrupts off and the port lock - * taken. - */ - spin_lock_irqsave(&port->lock, flags); - do { - spin_unlock_irqrestore(&port->lock, flags); - spin_lock_irqsave(&port->lock, flags); - prev_tr_ctrl = tr_ctrl = REG_RD(ser, regi_ser, rw_tr_ctrl); - rstat = REG_RD(ser, regi_ser, r_stat_din); - } while (!rstat.tr_rdy); - - /* - * Ack an interrupt if one was just issued for the previous character - * that was output. This is required for non-DMA as the interrupt is - * used as the only indicator that the transmitter is ready and it - * isn't while this x_char is being transmitted. - */ - REG_WR(ser, regi_ser, rw_ack_intr, ack_intr); - - /* Enable the transmitter in case it was disabled. */ - tr_ctrl.stop = 0; - REG_WR(ser, regi_ser, rw_tr_ctrl, tr_ctrl); - - /* - * Finally, send the blessed character; nothing should stop it now, - * except for an xoff-detected state, which we'll handle below. - */ - REG_WR(ser, regi_ser, rw_dout, dout); - up->port.icount.tx++; - - /* There might be an xoff state to clear. */ - rstat = REG_RD(ser, up->regi_ser, r_stat_din); - - /* - * Clear any xoff state that *may* have been there to - * inhibit transmission of the character. - */ - if (rstat.xoff_detect) { - reg_ser_rw_xoff_clr xoff_clr = { .clr = 1 }; - reg_ser_rw_tr_dma_en tr_dma_en; - - REG_WR(ser, regi_ser, rw_xoff_clr, xoff_clr); - tr_dma_en = REG_RD(ser, regi_ser, rw_tr_dma_en); - - /* - * If we had an xoff state but cleared it, instead sneak in a - * disabled state for the transmitter, after the character we - * sent. Thus we keep the port disabled, just as if the xoff - * state was still in effect (or actually, as if stop_tx had - * been called, as we stop DMA too). - */ - prev_tr_ctrl.stop = 1; - - tr_dma_en.en = 0; - REG_WR(ser, regi_ser, rw_tr_dma_en, tr_dma_en); - } - - /* Restore "previous" enabled/disabled state of the transmitter. */ - REG_WR(ser, regi_ser, rw_tr_ctrl, prev_tr_ctrl); - - spin_unlock_irqrestore(&port->lock, flags); -} - -/* - * Do not spin_lock_irqsave or disable interrupts by other means here; it's - * already done by the caller. - */ -static void etraxfs_uart_start_tx(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - - /* we have already done below if a write is ongoing */ - if (up->write_ongoing) - return; - - /* Signal that write is ongoing */ - up->write_ongoing = 1; - - etraxfs_uart_start_tx_bottom(port); -} - -static inline void etraxfs_uart_start_tx_bottom(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - void __iomem *regi_ser = up->regi_ser; - reg_ser_rw_tr_ctrl tr_ctrl; - reg_ser_rw_intr_mask intr_mask; - - tr_ctrl = REG_RD(ser, regi_ser, rw_tr_ctrl); - tr_ctrl.stop = regk_ser_no; - REG_WR(ser, regi_ser, rw_tr_ctrl, tr_ctrl); - intr_mask = REG_RD(ser, regi_ser, rw_intr_mask); - intr_mask.tr_rdy = regk_ser_yes; - REG_WR(ser, regi_ser, rw_intr_mask, intr_mask); -} - -/* - * This function handles both the DMA and non-DMA case by ordering the - * transmitter to stop of after the current character. We don't need to wait - * for any such character to be completely transmitted; we do that where it - * matters, like in etraxfs_uart_set_termios. Don't busy-wait here; see - * Documentation/serial/driver: this function is called within - * spin_lock_irq{,save} and thus separate ones would be disastrous (when SMP). - * There's no documented need to set the txd pin to any particular value; - * break setting is controlled solely by etraxfs_uart_break_ctl. - */ -static void etraxfs_uart_stop_tx(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - void __iomem *regi_ser = up->regi_ser; - reg_ser_rw_tr_ctrl tr_ctrl; - reg_ser_rw_intr_mask intr_mask; - reg_ser_rw_tr_dma_en tr_dma_en = {0}; - reg_ser_rw_xoff_clr xoff_clr = {0}; - - /* - * For the non-DMA case, we'd get a tr_rdy interrupt that we're not - * interested in as we're not transmitting any characters. For the - * DMA case, that interrupt is already turned off, but no reason to - * waste code on conditionals here. - */ - intr_mask = REG_RD(ser, regi_ser, rw_intr_mask); - intr_mask.tr_rdy = regk_ser_no; - REG_WR(ser, regi_ser, rw_intr_mask, intr_mask); - - tr_ctrl = REG_RD(ser, regi_ser, rw_tr_ctrl); - tr_ctrl.stop = 1; - REG_WR(ser, regi_ser, rw_tr_ctrl, tr_ctrl); - - /* - * Always clear possible hardware xoff-detected state here, no need to - * unnecessary consider mctrl settings and when they change. We clear - * it here rather than in start_tx: both functions are called as the - * effect of XOFF processing, but start_tx is also called when upper - * levels tell the driver that there are more characters to send, so - * avoid adding code there. - */ - xoff_clr.clr = 1; - REG_WR(ser, regi_ser, rw_xoff_clr, xoff_clr); - - /* - * Disable transmitter DMA, so that if we're in XON/XOFF, we can send - * those single characters without also giving go-ahead for queued up - * DMA data. - */ - tr_dma_en.en = 0; - REG_WR(ser, regi_ser, rw_tr_dma_en, tr_dma_en); - - /* - * Make sure that write_ongoing is reset when stopping tx. - */ - up->write_ongoing = 0; -} - -static void etraxfs_uart_stop_rx(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - void __iomem *regi_ser = up->regi_ser; - reg_ser_rw_rec_ctrl rec_ctrl = REG_RD(ser, regi_ser, rw_rec_ctrl); - - rec_ctrl.en = regk_ser_no; - REG_WR(ser, regi_ser, rw_rec_ctrl, rec_ctrl); -} - -static unsigned int etraxfs_uart_tx_empty(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned long flags; - unsigned int ret; - reg_ser_r_stat_din rstat = {0}; - - spin_lock_irqsave(&up->port.lock, flags); - - rstat = REG_RD(ser, up->regi_ser, r_stat_din); - ret = rstat.tr_empty ? TIOCSER_TEMT : 0; - - spin_unlock_irqrestore(&up->port.lock, flags); - return ret; -} -static unsigned int etraxfs_uart_get_mctrl(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned int ret; - - ret = 0; - if (crisv32_serial_get_rts(up)) - ret |= TIOCM_RTS; - if (crisv32_serial_get_cts(up)) - ret |= TIOCM_CTS; - return mctrl_gpio_get(up->gpios, &ret); -} - -static void etraxfs_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - - crisv32_serial_set_rts(up, mctrl & TIOCM_RTS ? 1 : 0, 0); - mctrl_gpio_set(up->gpios, mctrl); -} - -static void etraxfs_uart_break_ctl(struct uart_port *port, int break_state) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned long flags; - reg_ser_rw_tr_ctrl tr_ctrl; - reg_ser_rw_tr_dma_en tr_dma_en; - reg_ser_rw_intr_mask intr_mask; - - spin_lock_irqsave(&up->port.lock, flags); - tr_ctrl = REG_RD(ser, up->regi_ser, rw_tr_ctrl); - tr_dma_en = REG_RD(ser, up->regi_ser, rw_tr_dma_en); - intr_mask = REG_RD(ser, up->regi_ser, rw_intr_mask); - - if (break_state != 0) { /* Send break */ - /* - * We need to disable DMA (if used) or tr_rdy interrupts if no - * DMA. No need to make this conditional on use of DMA; - * disabling will be a no-op for the other mode. - */ - intr_mask.tr_rdy = regk_ser_no; - tr_dma_en.en = 0; - - /* - * Stop transmission and set the txd pin to 0 after the - * current character. The txd setting will take effect after - * any current transmission has completed. - */ - tr_ctrl.stop = 1; - tr_ctrl.txd = 0; - } else { - /* Re-enable the serial interrupt. */ - intr_mask.tr_rdy = regk_ser_yes; - - tr_ctrl.stop = 0; - tr_ctrl.txd = 1; - } - REG_WR(ser, up->regi_ser, rw_tr_ctrl, tr_ctrl); - REG_WR(ser, up->regi_ser, rw_tr_dma_en, tr_dma_en); - REG_WR(ser, up->regi_ser, rw_intr_mask, intr_mask); - - spin_unlock_irqrestore(&up->port.lock, flags); -} - -static void -transmit_chars_no_dma(struct uart_cris_port *up) -{ - int max_count; - struct circ_buf *xmit = &up->port.state->xmit; - - void __iomem *regi_ser = up->regi_ser; - reg_ser_r_stat_din rstat; - reg_ser_rw_ack_intr ack_intr = { .tr_rdy = regk_ser_yes }; - - if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { - /* No more to send, so disable the interrupt. */ - reg_ser_rw_intr_mask intr_mask; - - intr_mask = REG_RD(ser, regi_ser, rw_intr_mask); - intr_mask.tr_rdy = 0; - intr_mask.tr_empty = 0; - REG_WR(ser, regi_ser, rw_intr_mask, intr_mask); - up->write_ongoing = 0; - return; - } - - /* If the serport is fast, we send up to max_count bytes before - exiting the loop. */ - max_count = 64; - do { - reg_ser_rw_dout dout = { .data = xmit->buf[xmit->tail] }; - - REG_WR(ser, regi_ser, rw_dout, dout); - REG_WR(ser, regi_ser, rw_ack_intr, ack_intr); - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE-1); - up->port.icount.tx++; - if (xmit->head == xmit->tail) - break; - rstat = REG_RD(ser, regi_ser, r_stat_din); - } while ((--max_count > 0) && rstat.tr_rdy); - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&up->port); -} - -static void receive_chars_no_dma(struct uart_cris_port *up) -{ - reg_ser_rs_stat_din stat_din; - reg_ser_r_stat_din rstat; - struct tty_port *port; - struct uart_icount *icount; - int max_count = 16; - char flag; - reg_ser_rw_ack_intr ack_intr = { 0 }; - - rstat = REG_RD(ser, up->regi_ser, r_stat_din); - icount = &up->port.icount; - port = &up->port.state->port; - - do { - stat_din = REG_RD(ser, up->regi_ser, rs_stat_din); - - flag = TTY_NORMAL; - ack_intr.dav = 1; - REG_WR(ser, up->regi_ser, rw_ack_intr, ack_intr); - icount->rx++; - - if (stat_din.framing_err | stat_din.par_err | stat_din.orun) { - if (stat_din.data == 0x00 && - stat_din.framing_err) { - /* Most likely a break. */ - flag = TTY_BREAK; - icount->brk++; - } else if (stat_din.par_err) { - flag = TTY_PARITY; - icount->parity++; - } else if (stat_din.orun) { - flag = TTY_OVERRUN; - icount->overrun++; - } else if (stat_din.framing_err) { - flag = TTY_FRAME; - icount->frame++; - } - } - - /* - * If this becomes important, we probably *could* handle this - * gracefully by keeping track of the unhandled character. - */ - if (!tty_insert_flip_char(port, stat_din.data, flag)) - panic("%s: No tty buffer space", __func__); - rstat = REG_RD(ser, up->regi_ser, r_stat_din); - } while (rstat.dav && (max_count-- > 0)); - spin_unlock(&up->port.lock); - tty_flip_buffer_push(port); - spin_lock(&up->port.lock); -} - -static irqreturn_t -ser_interrupt(int irq, void *dev_id) -{ - struct uart_cris_port *up = (struct uart_cris_port *)dev_id; - void __iomem *regi_ser; - int handled = 0; - - spin_lock(&up->port.lock); - - regi_ser = up->regi_ser; - - if (regi_ser) { - reg_ser_r_masked_intr masked_intr; - - masked_intr = REG_RD(ser, regi_ser, r_masked_intr); - /* - * Check what interrupts are active before taking - * actions. If DMA is used the interrupt shouldn't - * be enabled. - */ - if (masked_intr.dav) { - receive_chars_no_dma(up); - handled = 1; - } - - if (masked_intr.tr_rdy) { - transmit_chars_no_dma(up); - handled = 1; - } - } - spin_unlock(&up->port.lock); - return IRQ_RETVAL(handled); -} - -#ifdef CONFIG_CONSOLE_POLL -static int etraxfs_uart_get_poll_char(struct uart_port *port) -{ - reg_ser_rs_stat_din stat; - reg_ser_rw_ack_intr ack_intr = { 0 }; - struct uart_cris_port *up = (struct uart_cris_port *)port; - - do { - stat = REG_RD(ser, up->regi_ser, rs_stat_din); - } while (!stat.dav); - - /* Ack the data_avail interrupt. */ - ack_intr.dav = 1; - REG_WR(ser, up->regi_ser, rw_ack_intr, ack_intr); - - return stat.data; -} - -static void etraxfs_uart_put_poll_char(struct uart_port *port, - unsigned char c) -{ - reg_ser_r_stat_din stat; - struct uart_cris_port *up = (struct uart_cris_port *)port; - - do { - stat = REG_RD(ser, up->regi_ser, r_stat_din); - } while (!stat.tr_rdy); - REG_WR_INT(ser, up->regi_ser, rw_dout, c); -} -#endif /* CONFIG_CONSOLE_POLL */ - -static int etraxfs_uart_startup(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned long flags; - reg_ser_rw_intr_mask ser_intr_mask = {0}; - - ser_intr_mask.dav = regk_ser_yes; - - if (request_irq(etraxfs_uart_ports[port->line]->irq, ser_interrupt, - 0, DRV_NAME, etraxfs_uart_ports[port->line])) - panic("irq ser%d", port->line); - - spin_lock_irqsave(&up->port.lock, flags); - - REG_WR(ser, up->regi_ser, rw_intr_mask, ser_intr_mask); - - etraxfs_uart_set_mctrl(&up->port, up->port.mctrl); - - spin_unlock_irqrestore(&up->port.lock, flags); - - return 0; -} - -static void etraxfs_uart_shutdown(struct uart_port *port) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned long flags; - - spin_lock_irqsave(&up->port.lock, flags); - - etraxfs_uart_stop_tx(port); - etraxfs_uart_stop_rx(port); - - free_irq(etraxfs_uart_ports[port->line]->irq, - etraxfs_uart_ports[port->line]); - - etraxfs_uart_set_mctrl(&up->port, up->port.mctrl); - - spin_unlock_irqrestore(&up->port.lock, flags); - -} - -static void -etraxfs_uart_set_termios(struct uart_port *port, struct ktermios *termios, - struct ktermios *old) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - unsigned long flags; - reg_ser_rw_xoff xoff; - reg_ser_rw_xoff_clr xoff_clr = {0}; - reg_ser_rw_tr_ctrl tx_ctrl = {0}; - reg_ser_rw_tr_dma_en tx_dma_en = {0}; - reg_ser_rw_rec_ctrl rx_ctrl = {0}; - reg_ser_rw_tr_baud_div tx_baud_div = {0}; - reg_ser_rw_rec_baud_div rx_baud_div = {0}; - int baud; - - if (old && - termios->c_cflag == old->c_cflag && - termios->c_iflag == old->c_iflag) - return; - - /* Tx: 8 bit, no/even parity, 1 stop bit, no cts. */ - tx_ctrl.base_freq = regk_ser_f29_493; - tx_ctrl.en = 0; - tx_ctrl.stop = 0; - tx_ctrl.auto_rts = regk_ser_no; - tx_ctrl.txd = 1; - tx_ctrl.auto_cts = 0; - /* Rx: 8 bit, no/even parity. */ - rx_ctrl.dma_err = regk_ser_stop; - rx_ctrl.sampling = regk_ser_majority; - rx_ctrl.timeout = 1; - - rx_ctrl.rts_n = regk_ser_inactive; - - /* Common for tx and rx: 8N1. */ - tx_ctrl.data_bits = regk_ser_bits8; - rx_ctrl.data_bits = regk_ser_bits8; - tx_ctrl.par = regk_ser_even; - rx_ctrl.par = regk_ser_even; - tx_ctrl.par_en = regk_ser_no; - rx_ctrl.par_en = regk_ser_no; - - tx_ctrl.stop_bits = regk_ser_bits1; - - /* - * Change baud-rate and write it to the hardware. - * - * baud_clock = base_freq / (divisor*8) - * divisor = base_freq / (baud_clock * 8) - * base_freq is either: - * off, ext, 29.493MHz, 32.000 MHz, 32.768 MHz or 100 MHz - * 20.493MHz is used for standard baudrates - */ - - /* - * For the console port we keep the original baudrate here. Not very - * beautiful. - */ - if ((port != console_port) || old) - baud = uart_get_baud_rate(port, termios, old, 0, - port->uartclk / 8); - else - baud = console_baud; - - tx_baud_div.div = 29493000 / (8 * baud); - /* Rx uses same as tx. */ - rx_baud_div.div = tx_baud_div.div; - rx_ctrl.base_freq = tx_ctrl.base_freq; - - if ((termios->c_cflag & CSIZE) == CS7) { - /* Set 7 bit mode. */ - tx_ctrl.data_bits = regk_ser_bits7; - rx_ctrl.data_bits = regk_ser_bits7; - } - - if (termios->c_cflag & CSTOPB) { - /* Set 2 stop bit mode. */ - tx_ctrl.stop_bits = regk_ser_bits2; - } - - if (termios->c_cflag & PARENB) { - /* Enable parity. */ - tx_ctrl.par_en = regk_ser_yes; - rx_ctrl.par_en = regk_ser_yes; - } - - if (termios->c_cflag & CMSPAR) { - if (termios->c_cflag & PARODD) { - /* Set mark parity if PARODD and CMSPAR. */ - tx_ctrl.par = regk_ser_mark; - rx_ctrl.par = regk_ser_mark; - } else { - tx_ctrl.par = regk_ser_space; - rx_ctrl.par = regk_ser_space; - } - } else { - if (termios->c_cflag & PARODD) { - /* Set odd parity. */ - tx_ctrl.par = regk_ser_odd; - rx_ctrl.par = regk_ser_odd; - } - } - - if (termios->c_cflag & CRTSCTS) { - /* Enable automatic CTS handling. */ - tx_ctrl.auto_cts = regk_ser_yes; - } - - /* Make sure the tx and rx are enabled. */ - tx_ctrl.en = regk_ser_yes; - rx_ctrl.en = regk_ser_yes; - - spin_lock_irqsave(&port->lock, flags); - - tx_dma_en.en = 0; - REG_WR(ser, up->regi_ser, rw_tr_dma_en, tx_dma_en); - - /* Actually write the control regs (if modified) to the hardware. */ - uart_update_timeout(port, termios->c_cflag, port->uartclk/8); - MODIFY_REG(up->regi_ser, rw_rec_baud_div, rx_baud_div); - MODIFY_REG(up->regi_ser, rw_rec_ctrl, rx_ctrl); - - MODIFY_REG(up->regi_ser, rw_tr_baud_div, tx_baud_div); - MODIFY_REG(up->regi_ser, rw_tr_ctrl, tx_ctrl); - - tx_dma_en.en = 0; - REG_WR(ser, up->regi_ser, rw_tr_dma_en, tx_dma_en); - - xoff = REG_RD(ser, up->regi_ser, rw_xoff); - - if (up->port.state && up->port.state->port.tty && - (up->port.state->port.tty->termios.c_iflag & IXON)) { - xoff.chr = STOP_CHAR(up->port.state->port.tty); - xoff.automatic = regk_ser_yes; - } else - xoff.automatic = regk_ser_no; - - MODIFY_REG(up->regi_ser, rw_xoff, xoff); - - /* - * Make sure we don't start in an automatically shut-off state due to - * a previous early exit. - */ - xoff_clr.clr = 1; - REG_WR(ser, up->regi_ser, rw_xoff_clr, xoff_clr); - - etraxfs_uart_set_mctrl(&up->port, up->port.mctrl); - spin_unlock_irqrestore(&up->port.lock, flags); -} - -static const char * -etraxfs_uart_type(struct uart_port *port) -{ - return "CRISv32"; -} - -static void etraxfs_uart_release_port(struct uart_port *port) -{ -} - -static int etraxfs_uart_request_port(struct uart_port *port) -{ - return 0; -} - -static void etraxfs_uart_config_port(struct uart_port *port, int flags) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - - up->port.type = PORT_CRIS; -} - -static const struct uart_ops etraxfs_uart_pops = { - .tx_empty = etraxfs_uart_tx_empty, - .set_mctrl = etraxfs_uart_set_mctrl, - .get_mctrl = etraxfs_uart_get_mctrl, - .stop_tx = etraxfs_uart_stop_tx, - .start_tx = etraxfs_uart_start_tx, - .send_xchar = etraxfs_uart_send_xchar, - .stop_rx = etraxfs_uart_stop_rx, - .break_ctl = etraxfs_uart_break_ctl, - .startup = etraxfs_uart_startup, - .shutdown = etraxfs_uart_shutdown, - .set_termios = etraxfs_uart_set_termios, - .type = etraxfs_uart_type, - .release_port = etraxfs_uart_release_port, - .request_port = etraxfs_uart_request_port, - .config_port = etraxfs_uart_config_port, -#ifdef CONFIG_CONSOLE_POLL - .poll_get_char = etraxfs_uart_get_poll_char, - .poll_put_char = etraxfs_uart_put_poll_char, -#endif -}; - -static void cris_serial_port_init(struct uart_port *port, int line) -{ - struct uart_cris_port *up = (struct uart_cris_port *)port; - - if (up->initialized) - return; - up->initialized = 1; - port->line = line; - spin_lock_init(&port->lock); - port->ops = &etraxfs_uart_pops; - port->irq = up->irq; - port->iobase = (unsigned long) up->regi_ser; - port->uartclk = 29493000; - - /* - * We can't fit any more than 255 here (unsigned char), though - * actually UART_XMIT_SIZE characters could be pending output. - * At time of this writing, the definition of "fifosize" is here the - * amount of characters that can be pending output after a start_tx call - * until tx_empty returns 1: see serial_core.c:uart_wait_until_sent. - * This matters for timeout calculations unfortunately, but keeping - * larger amounts at the DMA wouldn't win much so let's just play nice. - */ - port->fifosize = 255; - port->flags = UPF_BOOT_AUTOCONF; -} - -static int etraxfs_uart_probe(struct platform_device *pdev) -{ - struct device_node *np = pdev->dev.of_node; - struct uart_cris_port *up; - int dev_id; - - if (!np) - return -ENODEV; - - dev_id = of_alias_get_id(np, "serial"); - if (dev_id < 0) - dev_id = 0; - - if (dev_id >= UART_NR) - return -EINVAL; - - if (etraxfs_uart_ports[dev_id]) - return -EBUSY; - - up = devm_kzalloc(&pdev->dev, sizeof(struct uart_cris_port), - GFP_KERNEL); - if (!up) - return -ENOMEM; - - up->irq = irq_of_parse_and_map(np, 0); - up->regi_ser = of_iomap(np, 0); - up->port.dev = &pdev->dev; - - up->gpios = mctrl_gpio_init_noauto(&pdev->dev, 0); - if (IS_ERR(up->gpios)) - return PTR_ERR(up->gpios); - - cris_serial_port_init(&up->port, dev_id); - - etraxfs_uart_ports[dev_id] = up; - platform_set_drvdata(pdev, &up->port); - uart_add_one_port(&etraxfs_uart_driver, &up->port); - - return 0; -} - -static int etraxfs_uart_remove(struct platform_device *pdev) -{ - struct uart_port *port; - - port = platform_get_drvdata(pdev); - uart_remove_one_port(&etraxfs_uart_driver, port); - etraxfs_uart_ports[port->line] = NULL; - - return 0; -} - -static const struct of_device_id etraxfs_uart_dt_ids[] = { - { .compatible = "axis,etraxfs-uart" }, - { /* sentinel */ } -}; - -MODULE_DEVICE_TABLE(of, etraxfs_uart_dt_ids); - -static struct platform_driver etraxfs_uart_platform_driver = { - .driver = { - .name = DRV_NAME, - .of_match_table = of_match_ptr(etraxfs_uart_dt_ids), - }, - .probe = etraxfs_uart_probe, - .remove = etraxfs_uart_remove, -}; - -static int __init etraxfs_uart_init(void) -{ - int ret; - - ret = uart_register_driver(&etraxfs_uart_driver); - if (ret) - return ret; - - ret = platform_driver_register(&etraxfs_uart_platform_driver); - if (ret) - uart_unregister_driver(&etraxfs_uart_driver); - - return ret; -} - -static void __exit etraxfs_uart_exit(void) -{ - platform_driver_unregister(&etraxfs_uart_platform_driver); - uart_unregister_driver(&etraxfs_uart_driver); -} - -module_init(etraxfs_uart_init); -module_exit(etraxfs_uart_exit); |