Commit 4409df58 authored by Hugo Villeneuve's avatar Hugo Villeneuve Committed by Greg Kroah-Hartman
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serial: sc16is7xx: change EFR lock to operate on each channels 



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: 3837a037 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port")
Cc:  <stable@vger.kernel.org> # 6.1.x: 3837a037 serial: sc16is7xx: improve regmap debugfs by using one regmap per port
Signed-off-by: default avatarHugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231211171353.2901416-5-hugo@hugovil.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 41a308cb

drivers/tty/serial/sc16is7xx.c

+26 −23
Original line number Diff line number Diff line
@@ -323,6 +323,7 @@ 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;
@@ -342,7 +343,6 @@ 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[];

};
@@ -494,7 +494,6 @@ static bool sc16is7xx_regmap_precious(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;

	u8 prescaler = 0;
@@ -518,7 +517,7 @@ 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);
@@ -537,7 +536,7 @@ 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);



	sc16is7xx_port_update(port, SC16IS7XX_MCR_REG,

			      SC16IS7XX_MCR_CLKSEL_BIT,
@@ -705,11 +704,10 @@ static unsigned int sc16is7xx_get_hwmctrl(struct uart_port *port) 
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;
@@ -735,15 +733,20 @@ static void sc16is7xx_update_mlines(struct sc16is7xx_one *one) 


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;
@@ -783,15 +786,17 @@ 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;
@@ -802,24 +807,22 @@ 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);

	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);
@@ -926,9 +929,9 @@ static void sc16is7xx_ms_proc(struct kthread_work *ws) 
	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);

	}
@@ -1012,7 +1015,6 @@ static void sc16is7xx_set_termios(struct uart_port *port, 
				  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;
@@ -1071,7 +1073,7 @@ 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);
@@ -1101,7 +1103,7 @@ 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,
@@ -1535,7 +1537,6 @@ 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,
@@ -1578,6 +1579,8 @@ static int sc16is7xx_probe(struct device *dev, 
			goto out_ports;

		}



		mutex_init(&s->p[i].efr_lock);



		ret = uart_get_rs485_mode(&s->p[i].port);

		if (ret)

			goto out_ports;