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.
[Hui: fixed some conflict when backporting to 5.15.y]
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 Signed-off-by: Hui Wang hui.wang@canonical.com --- drivers/tty/serial/sc16is7xx.c | 41 +++++++++++++++++++--------------- 1 file changed, 23 insertions(+), 18 deletions(-)
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index a2d05dd5a339..692c14d7f7d1 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -314,6 +314,7 @@ 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 sc16is7xx_one_config config; @@ -329,7 +330,6 @@ 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[]; };
@@ -491,7 +491,6 @@ static bool sc16is7xx_regmap_noinc(struct device *dev, unsigned int reg) */ 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; unsigned int prescaler = 1; @@ -515,7 +514,7 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) * 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);
@@ -532,7 +531,7 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) /* 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);
/* If bit MCR_CLKSEL is set, the divide by 4 prescaler is activated. */ sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, @@ -680,14 +679,20 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
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;
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;
@@ -722,15 +727,17 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno) 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; @@ -741,23 +748,21 @@ static irqreturn_t sc16is7xx_irq(int irq, void *dev_id) 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);
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); }
static void sc16is7xx_reconf_rs485(struct uart_port *port) @@ -878,7 +883,6 @@ static void sc16is7xx_set_termios(struct uart_port *port, struct ktermios *termios, 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; @@ -934,7 +938,7 @@ static void sc16is7xx_set_termios(struct uart_port *port, 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); @@ -957,7 +961,7 @@ static void sc16is7xx_set_termios(struct uart_port *port, /* 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, @@ -1261,7 +1265,6 @@ static int sc16is7xx_probe(struct device *dev,
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, @@ -1302,6 +1305,8 @@ static int sc16is7xx_probe(struct device *dev, goto out_ports; }
+ mutex_init(&s->p[i].efr_lock); + /* Disable all interrupts */ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_IER_REG, 0); /* Disable TX/RX */