6.7-stable review patch. If anyone has any objections, please let me know.
------------------
From: Hugo Villeneuve hvilleneuve@dimonoff.com
commit 4409df5866b7ff7686ba27e449ca97a92ee063c9 upstream.
Now that the driver has been converted to use one regmap per port, change efr locking to operate on a channel basis instead of on the whole IC.
Fixes: 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") Cc: stable@vger.kernel.org # 6.1.x: 3837a03 serial: sc16is7xx: improve regmap debugfs by using one regmap per port Signed-off-by: Hugo Villeneuve hvilleneuve@dimonoff.com Link: https://lore.kernel.org/r/20231211171353.2901416-5-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/sc16is7xx.c | 49 +++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 23 deletions(-)
--- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -324,6 +324,7 @@ struct sc16is7xx_one_config { struct sc16is7xx_one { struct uart_port port; struct regmap *regmap; + struct mutex efr_lock; /* EFR registers access */ struct kthread_work tx_work; struct kthread_work reg_work; struct kthread_delayed_work ms_work; @@ -343,7 +344,6 @@ struct sc16is7xx_port { unsigned char buf[SC16IS7XX_FIFO_SIZE]; struct kthread_worker kworker; struct task_struct *kworker_task; - struct mutex efr_lock; struct sc16is7xx_one p[]; };
@@ -495,7 +495,6 @@ static bool sc16is7xx_regmap_precious(st
static int sc16is7xx_set_baud(struct uart_port *port, int baud) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); u8 lcr; u8 prescaler = 0; @@ -519,7 +518,7 @@ static int sc16is7xx_set_baud(struct uar * because the bulk of the interrupt processing is run as a workqueue * job in thread context. */ - mutex_lock(&s->efr_lock); + mutex_lock(&one->efr_lock);
lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
@@ -538,7 +537,7 @@ static int sc16is7xx_set_baud(struct uar /* Put LCR back to the normal mode */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
- mutex_unlock(&s->efr_lock); + mutex_unlock(&one->efr_lock);
sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, SC16IS7XX_MCR_CLKSEL_BIT, @@ -706,11 +705,10 @@ static unsigned int sc16is7xx_get_hwmctr static void sc16is7xx_update_mlines(struct sc16is7xx_one *one) { struct uart_port *port = &one->port; - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); unsigned long flags; unsigned int status, changed;
- lockdep_assert_held_once(&s->efr_lock); + lockdep_assert_held_once(&one->efr_lock);
status = sc16is7xx_get_hwmctrl(port); changed = status ^ one->old_mctrl; @@ -736,15 +734,20 @@ static void sc16is7xx_update_mlines(stru
static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno) { + bool rc = true; struct uart_port *port = &s->p[portno].port; + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); + + mutex_lock(&one->efr_lock);
do { unsigned int iir, rxlen; - struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
iir = sc16is7xx_port_read(port, SC16IS7XX_IIR_REG); - if (iir & SC16IS7XX_IIR_NO_INT_BIT) - return false; + if (iir & SC16IS7XX_IIR_NO_INT_BIT) { + rc = false; + goto out_port_irq; + }
iir &= SC16IS7XX_IIR_ID_MASK;
@@ -784,15 +787,17 @@ static bool sc16is7xx_port_irq(struct sc break; } } while (0); - return true; + +out_port_irq: + mutex_unlock(&one->efr_lock); + + return rc; }
static irqreturn_t sc16is7xx_irq(int irq, void *dev_id) { struct sc16is7xx_port *s = (struct sc16is7xx_port *)dev_id;
- mutex_lock(&s->efr_lock); - while (1) { bool keep_polling = false; int i; @@ -803,24 +808,22 @@ static irqreturn_t sc16is7xx_irq(int irq break; }
- mutex_unlock(&s->efr_lock); - return IRQ_HANDLED; }
static void sc16is7xx_tx_proc(struct kthread_work *ws) { struct uart_port *port = &(to_sc16is7xx_one(ws, tx_work)->port); - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); unsigned long flags;
if ((port->rs485.flags & SER_RS485_ENABLED) && (port->rs485.delay_rts_before_send > 0)) msleep(port->rs485.delay_rts_before_send);
- mutex_lock(&s->efr_lock); + mutex_lock(&one->efr_lock); sc16is7xx_handle_tx(port); - mutex_unlock(&s->efr_lock); + mutex_unlock(&one->efr_lock);
uart_port_lock_irqsave(port, &flags); sc16is7xx_ier_set(port, SC16IS7XX_IER_THRI_BIT); @@ -927,9 +930,9 @@ static void sc16is7xx_ms_proc(struct kth struct sc16is7xx_port *s = dev_get_drvdata(one->port.dev);
if (one->port.state) { - mutex_lock(&s->efr_lock); + mutex_lock(&one->efr_lock); sc16is7xx_update_mlines(one); - mutex_unlock(&s->efr_lock); + mutex_unlock(&one->efr_lock);
kthread_queue_delayed_work(&s->kworker, &one->ms_work, HZ); } @@ -1013,7 +1016,6 @@ static void sc16is7xx_set_termios(struct struct ktermios *termios, const struct ktermios *old) { - struct sc16is7xx_port *s = dev_get_drvdata(port->dev); struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); unsigned int lcr, flow = 0; int baud; @@ -1072,7 +1074,7 @@ static void sc16is7xx_set_termios(struct port->ignore_status_mask |= SC16IS7XX_LSR_BRK_ERROR_MASK;
/* As above, claim the mutex while accessing the EFR. */ - mutex_lock(&s->efr_lock); + mutex_lock(&one->efr_lock);
sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_CONF_MODE_B); @@ -1102,7 +1104,7 @@ static void sc16is7xx_set_termios(struct /* Update LCR register */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
- mutex_unlock(&s->efr_lock); + mutex_unlock(&one->efr_lock);
/* Get baud rate generator configuration */ baud = uart_get_baud_rate(port, termios, old, @@ -1536,7 +1538,6 @@ static int sc16is7xx_probe(struct device
s->devtype = devtype; dev_set_drvdata(dev, s); - mutex_init(&s->efr_lock);
kthread_init_worker(&s->kworker); s->kworker_task = kthread_run(kthread_worker_fn, &s->kworker, @@ -1579,6 +1580,8 @@ static int sc16is7xx_probe(struct device goto out_ports; }
+ mutex_init(&s->p[i].efr_lock); + ret = uart_get_rs485_mode(&s->p[i].port); if (ret) goto out_ports;