Commit 06d28ca0 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Greg Kroah-Hartman
Browse files

serial: pch: Remove eg20t_port::lock. 



The struct eg20t_port has a spinlock_t which is used for locking while
access I/O of the device. Then there is the uart_portlock which is
sometimes and nests within eg20t_port's lock.

The uart_port lock is not used while using the struct in
pch_uart_hal_read() which might be okay. Then both locks are used in
pch_console_write() which looks odd especially the double try_lock part.

All in all it looks like the uart_port's lock could replace eg20t_port's
lock and simplify the code.

Remove eg20t_port::lock and use uart_port's lock for the lock scope.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240301215246.891055-18-bigeasy@linutronix.de


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 38f3fc2e

drivers/tty/serial/pch_uart.c

+6 −20
Original line number Diff line number Diff line
@@ -237,9 +237,6 @@ struct eg20t_port { 


#define IRQ_NAME_SIZE 17

	char				irq_name[IRQ_NAME_SIZE];



	/* protect the eg20t_port private structure and io access to membase */

	spinlock_t lock;

};



/**
@@ -1013,7 +1010,7 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id) 
	int next = 1;

	u8 msr;



	spin_lock(&priv->lock);

	uart_port_lock(&priv->port);

	handled = 0;

	while (next) {

		iid = pch_uart_hal_get_iid(priv);
@@ -1073,7 +1070,7 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id) 
		handled |= (unsigned int)ret;

	}



	spin_unlock(&priv->lock);

	uart_port_unlock(&priv->port);

	return IRQ_RETVAL(handled);

}
@@ -1184,9 +1181,9 @@ static void pch_uart_break_ctl(struct uart_port *port, int ctl) 
	unsigned long flags;



	priv = container_of(port, struct eg20t_port, port);

	spin_lock_irqsave(&priv->lock, flags);

	uart_port_lock_irqsave(&priv->port, &flags);

	pch_uart_hal_set_break(priv, ctl);

	spin_unlock_irqrestore(&priv->lock, flags);

	uart_port_unlock_irqrestore(&priv->port, flags);

}



/* Grab any interrupt resources and initialise any low level driver state. */
@@ -1336,8 +1333,7 @@ static void pch_uart_set_termios(struct uart_port *port, 


	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);



	spin_lock_irqsave(&priv->lock, flags);

	uart_port_lock(port);

	uart_port_lock_irqsave(port, &flags);



	uart_update_timeout(port, termios->c_cflag, baud);

	rtn = pch_uart_hal_set_line(priv, baud, parity, bits, stb);
@@ -1350,8 +1346,7 @@ static void pch_uart_set_termios(struct uart_port *port, 
		tty_termios_encode_baud_rate(termios, baud, baud);



out:

	uart_port_unlock(port);

	spin_unlock_irqrestore(&priv->lock, flags);

	uart_port_unlock_irqrestore(port, flags);

}



static const char *pch_uart_type(struct uart_port *port)
@@ -1555,7 +1550,6 @@ pch_console_write(struct console *co, const char *s, unsigned int count) 
{

	struct eg20t_port *priv;

	unsigned long flags;

	int priv_locked = 1;

	int port_locked = 1;

	u8 ier;
@@ -1565,15 +1559,11 @@ pch_console_write(struct console *co, const char *s, unsigned int count) 


	local_irq_save(flags);

	if (priv->port.sysrq) {

		/* call to uart_handle_sysrq_char already took the priv lock */

		priv_locked = 0;

		/* serial8250_handle_port() already took the port lock */

		port_locked = 0;

	} else if (oops_in_progress) {

		priv_locked = spin_trylock(&priv->lock);

		port_locked = uart_port_trylock(&priv->port);

	} else {

		spin_lock(&priv->lock);

		uart_port_lock(&priv->port);

	}
@@ -1595,8 +1585,6 @@ pch_console_write(struct console *co, const char *s, unsigned int count) 


	if (port_locked)

		uart_port_unlock(&priv->port);

	if (priv_locked)

		spin_unlock(&priv->lock);

	local_irq_restore(flags);

}
@@ -1694,8 +1682,6 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev, 
	pci_enable_msi(pdev);

	pci_set_master(pdev);



	spin_lock_init(&priv->lock);



	iobase = pci_resource_start(pdev, 0);

	mapbase = pci_resource_start(pdev, 1);

	priv->mapbase = mapbase;