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TTY/Serial driver fixes for 6.1-rc6

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Here are a number of small tty and serial driver fixes for 6.1-rc6.
 They all resolve reported problems:
 	- kernel doc build problems with the -rc1 serial driver
 	  documentation update
 	- n_gsm reported problems
 	- imx serial driver missing callback
 	- lots of tiny 8250 driver fixes for reported issues.
 
 All of these have been in linux-next for over a week with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver fixes from Greg KH:
 "Here are a number of small tty and serial driver fixes for 6.1-rc6.
  They all resolve reported problems:

   - kernel doc build problems with the -rc1 serial driver documentation
     update

   - n_gsm reported problems

   - imx serial driver missing callback

   - lots of tiny 8250 driver fixes for reported issues.

  All of these have been in linux-next for over a week with no reported
  problems"

* tag 'tty-6.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  docs/driver-api/miscellaneous: Remove kernel-doc of serial_core.c
  serial: 8250: Flush DMA Rx on RLSI
  serial: 8250_lpss: Use 16B DMA burst with Elkhart Lake
  serial: 8250_lpss: Configure DMA also w/o DMA filter
  serial: 8250: Fall back to non-DMA Rx if IIR_RDI occurs
  tty: n_gsm: fix sleep-in-atomic-context bug in gsm_control_send
  Revert "tty: n_gsm: replace kicktimer with delayed_work"
  Revert "tty: n_gsm: avoid call of sleeping functions from atomic context"
  serial: imx: Add missing .thaw_noirq hook
  tty: serial: fsl_lpuart: don't break the on-going transfer when global reset
  serial: 8250: omap: Flush PM QOS work on remove
  serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()
  serial: 8250_omap: remove wait loop from Errata i202 workaround
  serial: 8250: omap: Fix missing PM runtime calls for omap8250_set_mctrl()
  serial: 8250: 8250_omap: Avoid RS485 RTS glitch on ->set_termios()
This commit is contained in:
Linus Torvalds 2022-11-18 10:59:52 -08:00
commit 09389357e9
7 changed files with 138 additions and 91 deletions
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5
Documentation/driver-api/miscellaneous.rst
View file

@ -16,12 +16,11 @@ Parallel Port Devices
16x50 UART Driver
=================
.. kernel-doc:: drivers/tty/serial/serial_core.c
:export:
.. kernel-doc:: drivers/tty/serial/8250/8250_core.c
:export:
See serial/driver.rst for related APIs.
Pulse-Width Modulation (PWM)
============================

71
drivers/tty/n_gsm.c
View file

@ -264,7 +264,7 @@ struct gsm_mux {
bool constipated; /* Asked by remote to shut up */
bool has_devices; /* Devices were registered */
struct mutex tx_mutex;
spinlock_t tx_lock;
unsigned int tx_bytes; /* TX data outstanding */
#define TX_THRESH_HI 8192
#define TX_THRESH_LO 2048
@ -272,7 +272,7 @@ struct gsm_mux {
struct list_head tx_data_list; /* Pending data packets */
/* Control messages */
struct delayed_work kick_timeout; /* Kick TX queuing on timeout */
struct timer_list kick_timer; /* Kick TX queuing on timeout */
struct timer_list t2_timer; /* Retransmit timer for commands */
int cretries; /* Command retry counter */
struct gsm_control *pending_cmd;/* Our current pending command */
@ -700,6 +700,7 @@ static int gsm_send(struct gsm_mux *gsm, int addr, int cr, int control)
struct gsm_msg *msg;
u8 *dp;
int ocr;
unsigned long flags;
msg = gsm_data_alloc(gsm, addr, 0, control);
if (!msg)
@ -721,10 +722,10 @@ static int gsm_send(struct gsm_mux *gsm, int addr, int cr, int control)
gsm_print_packet("Q->", addr, cr, control, NULL, 0);
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
list_add_tail(&msg->list, &gsm->tx_ctrl_list);
gsm->tx_bytes += msg->len;
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
gsmld_write_trigger(gsm);
return 0;
@ -749,7 +750,7 @@ static void gsm_dlci_clear_queues(struct gsm_mux *gsm, struct gsm_dlci *dlci)
spin_unlock_irqrestore(&dlci->lock, flags);
/* Clear data packets in MUX write queue */
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
list_for_each_entry_safe(msg, nmsg, &gsm->tx_data_list, list) {
if (msg->addr != addr)
continue;
@ -757,7 +758,7 @@ static void gsm_dlci_clear_queues(struct gsm_mux *gsm, struct gsm_dlci *dlci)
list_del(&msg->list);
kfree(msg);
}
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
}
/**
@ -1028,7 +1029,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
gsm->tx_bytes += msg->len;
gsmld_write_trigger(gsm);
schedule_delayed_work(&gsm->kick_timeout, 10 * gsm->t1 * HZ / 100);
mod_timer(&gsm->kick_timer, jiffies + 10 * gsm->t1 * HZ / 100);
}
/**
@ -1043,9 +1044,10 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
{
mutex_lock(&dlci->gsm->tx_mutex);
unsigned long flags;
spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
__gsm_data_queue(dlci, msg);
mutex_unlock(&dlci->gsm->tx_mutex);
spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
/**
@ -1057,7 +1059,7 @@ static void gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
* is data. Keep to the MRU of the mux. This path handles the usual tty
* interface which is a byte stream with optional modem data.
*
* Caller must hold the tx_mutex of the mux.
* Caller must hold the tx_lock of the mux.
*/
static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
@ -1117,7 +1119,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
* is data. Keep to the MRU of the mux. This path handles framed data
* queued as skbuffs to the DLCI.
*
* Caller must hold the tx_mutex of the mux.
* Caller must hold the tx_lock of the mux.
*/
static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
@ -1133,7 +1135,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
if (dlci->adaption == 4)
overhead = 1;
/* dlci->skb is locked by tx_mutex */
/* dlci->skb is locked by tx_lock */
if (dlci->skb == NULL) {
dlci->skb = skb_dequeue_tail(&dlci->skb_list);
if (dlci->skb == NULL)
@ -1187,7 +1189,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
* Push an empty frame in to the transmit queue to update the modem status
* bits and to transmit an optional break.
*
* Caller must hold the tx_mutex of the mux.
* Caller must hold the tx_lock of the mux.
*/
static int gsm_dlci_modem_output(struct gsm_mux *gsm, struct gsm_dlci *dlci,
@ -1301,12 +1303,13 @@ static int gsm_dlci_data_sweep(struct gsm_mux *gsm)
static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
{
unsigned long flags;
int sweep;
if (dlci->constipated)
return;
mutex_lock(&dlci->gsm->tx_mutex);
spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
/* If we have nothing running then we need to fire up */
sweep = (dlci->gsm->tx_bytes < TX_THRESH_LO);
if (dlci->gsm->tx_bytes == 0) {
@ -1317,7 +1320,7 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
}
if (sweep)
gsm_dlci_data_sweep(dlci->gsm);
mutex_unlock(&dlci->gsm->tx_mutex);
spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
/*
@ -1708,7 +1711,7 @@ static struct gsm_control *gsm_control_send(struct gsm_mux *gsm,
unsigned int command, u8 *data, int clen)
{
struct gsm_control *ctrl = kzalloc(sizeof(struct gsm_control),
GFP_KERNEL);
GFP_ATOMIC);
unsigned long flags;
if (ctrl == NULL)
return NULL;
@ -2019,23 +2022,24 @@ static void gsm_dlci_command(struct gsm_dlci *dlci, const u8 *data, int len)
}
/**
* gsm_kick_timeout - transmit if possible
* @work: work contained in our gsm object
* gsm_kick_timer - transmit if possible
* @t: timer contained in our gsm object
*
* Transmit data from DLCIs if the queue is empty. We can't rely on
* a tty wakeup except when we filled the pipe so we need to fire off
* new data ourselves in other cases.
*/
static void gsm_kick_timeout(struct work_struct *work)
static void gsm_kick_timer(struct timer_list *t)
{
struct gsm_mux *gsm = container_of(work, struct gsm_mux, kick_timeout.work);
struct gsm_mux *gsm = from_timer(gsm, t, kick_timer);
unsigned long flags;
int sent = 0;
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
/* If we have nothing running then we need to fire up */
if (gsm->tx_bytes < TX_THRESH_LO)
sent = gsm_dlci_data_sweep(gsm);
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
if (sent && debug & DBG_DATA)
pr_info("%s TX queue stalled\n", __func__);
@ -2492,7 +2496,7 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc)
}
/* Finish outstanding timers, making sure they are done */
cancel_delayed_work_sync(&gsm->kick_timeout);
del_timer_sync(&gsm->kick_timer);
del_timer_sync(&gsm->t2_timer);
/* Finish writing to ldisc */
@ -2565,7 +2569,6 @@ static void gsm_free_mux(struct gsm_mux *gsm)
break;
}
}
mutex_destroy(&gsm->tx_mutex);
mutex_destroy(&gsm->mutex);
kfree(gsm->txframe);
kfree(gsm->buf);
@ -2637,15 +2640,15 @@ static struct gsm_mux *gsm_alloc_mux(void)
}
spin_lock_init(&gsm->lock);
mutex_init(&gsm->mutex);
mutex_init(&gsm->tx_mutex);
kref_init(&gsm->ref);
INIT_LIST_HEAD(&gsm->tx_ctrl_list);
INIT_LIST_HEAD(&gsm->tx_data_list);
INIT_DELAYED_WORK(&gsm->kick_timeout, gsm_kick_timeout);
timer_setup(&gsm->kick_timer, gsm_kick_timer, 0);
timer_setup(&gsm->t2_timer, gsm_control_retransmit, 0);
INIT_WORK(&gsm->tx_work, gsmld_write_task);
init_waitqueue_head(&gsm->event);
spin_lock_init(&gsm->control_lock);
spin_lock_init(&gsm->tx_lock);
gsm->t1 = T1;
gsm->t2 = T2;
@ -2670,7 +2673,6 @@ static struct gsm_mux *gsm_alloc_mux(void)
}
spin_unlock(&gsm_mux_lock);
if (i == MAX_MUX) {
mutex_destroy(&gsm->tx_mutex);
mutex_destroy(&gsm->mutex);
kfree(gsm->txframe);
kfree(gsm->buf);
@ -2826,16 +2828,17 @@ static void gsmld_write_trigger(struct gsm_mux *gsm)
static void gsmld_write_task(struct work_struct *work)
{
struct gsm_mux *gsm = container_of(work, struct gsm_mux, tx_work);
unsigned long flags;
int i, ret;
/* All outstanding control channel and control messages and one data
* frame is sent.
*/
ret = -ENODEV;
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
if (gsm->tty)
ret = gsm_data_kick(gsm);
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
if (ret >= 0)
for (i = 0; i < NUM_DLCI; i++)
@ -3042,6 +3045,7 @@ static ssize_t gsmld_write(struct tty_struct *tty, struct file *file,
const unsigned char *buf, size_t nr)
{
struct gsm_mux *gsm = tty->disc_data;
unsigned long flags;
int space;
int ret;
@ -3049,13 +3053,13 @@ static ssize_t gsmld_write(struct tty_struct *tty, struct file *file,
return -ENODEV;
ret = -ENOBUFS;
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
space = tty_write_room(tty);
if (space >= nr)
ret = tty->ops->write(tty, buf, nr);
else
set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
return ret;
}
@ -3352,13 +3356,14 @@ static struct tty_ldisc_ops tty_ldisc_packet = {
static void gsm_modem_upd_via_data(struct gsm_dlci *dlci, u8 brk)
{
struct gsm_mux *gsm = dlci->gsm;
unsigned long flags;
if (dlci->state != DLCI_OPEN || dlci->adaption != 2)
return;
mutex_lock(&gsm->tx_mutex);
spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_dlci_modem_output(gsm, dlci, brk);
mutex_unlock(&gsm->tx_mutex);
spin_unlock_irqrestore(&gsm->tx_lock, flags);
}
/**

17
drivers/tty/serial/8250/8250_lpss.c
View file

@ -174,6 +174,8 @@ static int ehl_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
*/
up->dma = dma;
lpss->dma_maxburst = 16;
port->set_termios = dw8250_do_set_termios;
return 0;
@ -277,8 +279,13 @@ static int lpss8250_dma_setup(struct lpss8250 *lpss, struct uart_8250_port *port
struct dw_dma_slave *rx_param, *tx_param;
struct device *dev = port->port.dev;
if (!lpss->dma_param.dma_dev)
if (!lpss->dma_param.dma_dev) {
dma = port->dma;
if (dma)
goto out_configuration_only;
return 0;
}
rx_param = devm_kzalloc(dev, sizeof(*rx_param), GFP_KERNEL);
if (!rx_param)
@ -289,16 +296,18 @@ static int lpss8250_dma_setup(struct lpss8250 *lpss, struct uart_8250_port *port
return -ENOMEM;
*rx_param = lpss->dma_param;
dma->rxconf.src_maxburst = lpss->dma_maxburst;
*tx_param = lpss->dma_param;
dma->txconf.dst_maxburst = lpss->dma_maxburst;
dma->fn = lpss8250_dma_filter;
dma->rx_param = rx_param;
dma->tx_param = tx_param;
port->dma = dma;
out_configuration_only:
dma->rxconf.src_maxburst = lpss->dma_maxburst;
dma->txconf.dst_maxburst = lpss->dma_maxburst;
return 0;
}

52
drivers/tty/serial/8250/8250_omap.c
View file

@ -157,7 +157,11 @@ static u32 uart_read(struct uart_8250_port *up, u32 reg)
return readl(up->port.membase + (reg << up->port.regshift));
}
static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
/*
* Called on runtime PM resume path from omap8250_restore_regs(), and
* omap8250_set_mctrl().
*/
static void __omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_8250_port *up = up_to_u8250p(port);
struct omap8250_priv *priv = up->port.private_data;
@ -181,6 +185,20 @@ static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
}
}
static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
int err;
err = pm_runtime_resume_and_get(port->dev);
if (err)
return;
__omap8250_set_mctrl(port, mctrl);
pm_runtime_mark_last_busy(port->dev);
pm_runtime_put_autosuspend(port->dev);
}
/*
* Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
* The access to uart register after MDR1 Access
@ -193,27 +211,10 @@ static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
static void omap_8250_mdr1_errataset(struct uart_8250_port *up,
struct omap8250_priv *priv)
{
u8 timeout = 255;
serial_out(up, UART_OMAP_MDR1, priv->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->port.dev, "Errata i202: timedout %x\n",
serial_in(up, UART_LSR));
break;
}
udelay(1);
}
}
static void omap_8250_get_divisor(struct uart_port *port, unsigned int baud,
@ -292,6 +293,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
{
struct omap8250_priv *priv = up->port.private_data;
struct uart_8250_dma *dma = up->dma;
u8 mcr = serial8250_in_MCR(up);
if (dma && dma->tx_running) {
/*
@ -308,7 +310,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
serial_out(up, UART_EFR, UART_EFR_ECB);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial8250_out_MCR(up, UART_MCR_TCRTLR);
serial8250_out_MCR(up, mcr | UART_MCR_TCRTLR);
serial_out(up, UART_FCR, up->fcr);
omap8250_update_scr(up, priv);
@ -324,7 +326,8 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
serial_out(up, UART_LCR, 0);
/* drop TCR + TLR access, we setup XON/XOFF later */
serial8250_out_MCR(up, up->mcr);
serial8250_out_MCR(up, mcr);
serial_out(up, UART_IER, up->ier);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
@ -341,7 +344,7 @@ static void omap8250_restore_regs(struct uart_8250_port *up)
omap8250_update_mdr1(up, priv);
up->port.ops->set_mctrl(&up->port, up->port.mctrl);
__omap8250_set_mctrl(&up->port, up->port.mctrl);
if (up->port.rs485.flags & SER_RS485_ENABLED)
serial8250_em485_stop_tx(up);
@ -669,7 +672,6 @@ static int omap_8250_startup(struct uart_port *port)
pm_runtime_get_sync(port->dev);
up->mcr = 0;
serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_out(up, UART_LCR, UART_LCR_WLEN8);
@ -1458,9 +1460,15 @@ static int omap8250_probe(struct platform_device *pdev)
static int omap8250_remove(struct platform_device *pdev)
{
struct omap8250_priv *priv = platform_get_drvdata(pdev);
int err;
err = pm_runtime_resume_and_get(&pdev->dev);
if (err)
return err;
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_put_sync(&pdev->dev);
flush_work(&priv->qos_work);
pm_runtime_disable(&pdev->dev);
serial8250_unregister_port(priv->line);
cpu_latency_qos_remove_request(&priv->pm_qos_request);

7
drivers/tty/serial/8250/8250_port.c
View file

@ -1897,10 +1897,13 @@ EXPORT_SYMBOL_GPL(serial8250_modem_status);
static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir)
{
switch (iir & 0x3f) {
case UART_IIR_RX_TIMEOUT:
serial8250_rx_dma_flush(up);
case UART_IIR_RDI:
if (!up->dma->rx_running)
break;
fallthrough;
case UART_IIR_RLSI:
case UART_IIR_RX_TIMEOUT:
serial8250_rx_dma_flush(up);
return true;
}
return up->dma->rx_dma(up);

76
drivers/tty/serial/fsl_lpuart.c
View file

@ -12,6 +12,7 @@
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
@ -404,33 +405,6 @@ static unsigned int lpuart_get_baud_clk_rate(struct lpuart_port *sport)
#define lpuart_enable_clks(x) __lpuart_enable_clks(x, true)
#define lpuart_disable_clks(x) __lpuart_enable_clks(x, false)
static int lpuart_global_reset(struct lpuart_port *sport)
{
struct uart_port *port = &sport->port;
void __iomem *global_addr;
int ret;
if (uart_console(port))
return 0;
ret = clk_prepare_enable(sport->ipg_clk);
if (ret) {
dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret);
return ret;
}
if (is_imx7ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) {
global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF;
writel(UART_GLOBAL_RST, global_addr);
usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
writel(0, global_addr);
usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
}
clk_disable_unprepare(sport->ipg_clk);
return 0;
}
static void lpuart_stop_tx(struct uart_port *port)
{
unsigned char temp;
@ -2636,6 +2610,54 @@ static const struct serial_rs485 lpuart_rs485_supported = {
/* delay_rts_* and RX_DURING_TX are not supported */
};
static int lpuart_global_reset(struct lpuart_port *sport)
{
struct uart_port *port = &sport->port;
void __iomem *global_addr;
unsigned long ctrl, bd;
unsigned int val = 0;
int ret;
ret = clk_prepare_enable(sport->ipg_clk);
if (ret) {
dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret);
return ret;
}
if (is_imx7ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) {
/*
* If the transmitter is used by earlycon, wait for transmit engine to
* complete and then reset.
*/
ctrl = lpuart32_read(port, UARTCTRL);
if (ctrl & UARTCTRL_TE) {
bd = lpuart32_read(&sport->port, UARTBAUD);
if (read_poll_timeout(lpuart32_tx_empty, val, val, 1, 100000, false,
port)) {
dev_warn(sport->port.dev,
"timeout waiting for transmit engine to complete\n");
clk_disable_unprepare(sport->ipg_clk);
return 0;
}
}
global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF;
writel(UART_GLOBAL_RST, global_addr);
usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
writel(0, global_addr);
usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
/* Recover the transmitter for earlycon. */
if (ctrl & UARTCTRL_TE) {
lpuart32_write(port, bd, UARTBAUD);
lpuart32_write(port, ctrl, UARTCTRL);
}
}
clk_disable_unprepare(sport->ipg_clk);
return 0;
}
static int lpuart_probe(struct platform_device *pdev)
{
const struct lpuart_soc_data *sdata = of_device_get_match_data(&pdev->dev);

1
drivers/tty/serial/imx.c
View file

@ -2594,6 +2594,7 @@ static const struct dev_pm_ops imx_uart_pm_ops = {
.suspend_noirq = imx_uart_suspend_noirq,
.resume_noirq = imx_uart_resume_noirq,
.freeze_noirq = imx_uart_suspend_noirq,
.thaw_noirq = imx_uart_resume_noirq,
.restore_noirq = imx_uart_resume_noirq,
.suspend = imx_uart_suspend,
.resume = imx_uart_resume,