Commit 470dfd80 authored by Sven Van Asbroeck's avatar Sven Van Asbroeck Committed by Jakub Kicinski
Browse files

lan743x: replace polling loop by wait_event_timeout() 



The driver's ISR sends a 'software interrupt' event to the probe()
thread using the following method:
- probe(): write 0 to flag, enable s/w interrupt
- probe(): poll on flag, relax using usleep_range()
- ISR    : write 1 to flag

Replace with wake_up() / wait_event_timeout(). Besides being easier
to get right, this abstraction has better timing and memory
consistency properties.

Tested-by: Sven Van Asbroeck <thesven73@gmail.com> # lan7430
Signed-off-by: default avatarSven Van Asbroeck <thesven73@gmail.com>
Link: https://lore.kernel.org/r/20201123191529.14908-2-TheSven73@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent c31799ba

drivers/net/ethernet/microchip/lan743x_main.c

+13 −15
Original line number Diff line number Diff line
@@ -146,7 +146,8 @@ static void lan743x_intr_software_isr(struct lan743x_adapter *adapter) 


	/* disable the interrupt to prevent repeated re-triggering */

	lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_SW_GP_);

	intr->software_isr_flag = 1;

	intr->software_isr_flag = true;

	wake_up(&intr->software_isr_wq);

}



static void lan743x_tx_isr(void *context, u32 int_sts, u32 flags)
@@ -343,27 +344,22 @@ irq_done: 
static int lan743x_intr_test_isr(struct lan743x_adapter *adapter)

{

	struct lan743x_intr *intr = &adapter->intr;

	int result = -ENODEV;

	int timeout = 10;

	int ret;



	intr->software_isr_flag = 0;

	intr->software_isr_flag = false;



	/* enable interrupt */

	/* enable and activate test interrupt */

	lan743x_csr_write(adapter, INT_EN_SET, INT_BIT_SW_GP_);



	/* activate interrupt here */

	lan743x_csr_write(adapter, INT_SET, INT_BIT_SW_GP_);

	while ((timeout > 0) && (!(intr->software_isr_flag))) {

		usleep_range(1000, 20000);

		timeout--;

	}



	if (intr->software_isr_flag)

		result = 0;

	ret = wait_event_timeout(intr->software_isr_wq,

				 intr->software_isr_flag,

				 msecs_to_jiffies(200));



	/* disable interrupts */

	/* disable test interrupt */

	lan743x_csr_write(adapter, INT_EN_CLR, INT_BIT_SW_GP_);

	return result;



	return ret > 0 ? 0 : -ENODEV;

}



static int lan743x_intr_register_isr(struct lan743x_adapter *adapter,
@@ -537,6 +533,8 @@ static int lan743x_intr_open(struct lan743x_adapter *adapter) 
		flags |= LAN743X_VECTOR_FLAG_SOURCE_ENABLE_R2C;

	}



	init_waitqueue_head(&intr->software_isr_wq);



	ret = lan743x_intr_register_isr(adapter, 0, flags,

					INT_BIT_ALL_RX_ | INT_BIT_ALL_TX_ |

					INT_BIT_ALL_OTHER_,

drivers/net/ethernet/microchip/lan743x_main.h

+2 −1
Original line number Diff line number Diff line
@@ -616,7 +616,8 @@ struct lan743x_intr { 
	int			number_of_vectors;

	bool			using_vectors;



	int			software_isr_flag;

	bool			software_isr_flag;

	wait_queue_head_t	software_isr_wq;

};



#define LAN743X_MAX_FRAME_SIZE			(9 * 1024)

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