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* [PATCH 1/2] net: can: sja1000: Replace mdelay with usleep_range in peak_pci_probe
@ 2018-04-11  1:42 Jia-Ju Bai
  2018-04-25 14:53 ` Marc Kleine-Budde
  0 siblings, 1 reply; 2+ messages in thread
From: Jia-Ju Bai @ 2018-04-11  1:42 UTC (permalink / raw)
  To: wg, mkl; +Cc: linux-can, netdev, linux-kernel, Jia-Ju Bai

peak_pci_probe() is never called in atomic context.

peak_pci_probe() is set as ".probe" in struct pci_driver.

Despite never getting called from atomic context, peak_pci_probe()
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 drivers/net/can/sja1000/peak_pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/sja1000/peak_pci.c b/drivers/net/can/sja1000/peak_pci.c
index 131026f..48cf821 100644
--- a/drivers/net/can/sja1000/peak_pci.c
+++ b/drivers/net/can/sja1000/peak_pci.c
@@ -608,7 +608,7 @@ static int peak_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	writeb(0x00, cfg_base + PITA_GPIOICR);
 	/* Toggle reset */
 	writeb(0x05, cfg_base + PITA_MISC + 3);
-	mdelay(5);
+	usleep_range(5000, 6000);
 	/* Leave parport mux mode */
 	writeb(0x04, cfg_base + PITA_MISC + 3);
 
-- 
1.9.1

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [PATCH 1/2] net: can: sja1000: Replace mdelay with usleep_range in peak_pci_probe
  2018-04-11  1:42 [PATCH 1/2] net: can: sja1000: Replace mdelay with usleep_range in peak_pci_probe Jia-Ju Bai
@ 2018-04-25 14:53 ` Marc Kleine-Budde
  0 siblings, 0 replies; 2+ messages in thread
From: Marc Kleine-Budde @ 2018-04-25 14:53 UTC (permalink / raw)
  To: Jia-Ju Bai, wg; +Cc: linux-can, netdev, linux-kernel


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On 04/11/2018 03:42 AM, Jia-Ju Bai wrote:
> peak_pci_probe() is never called in atomic context.
> 
> peak_pci_probe() is set as ".probe" in struct pci_driver.
> 
> Despite never getting called from atomic context, peak_pci_probe()
> calls mdelay() to busily wait.
> This is not necessary and can be replaced with usleep_range() to
> avoid busy waiting.
> 
> This is found by a static analysis tool named DCNS written by myself.
> And I also manually check it.
> 
> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>

Applied both to linux-can-next.

tnx,
Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


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^ permalink raw reply	[flat|nested] 2+ messages in thread

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2018-04-11  1:42 [PATCH 1/2] net: can: sja1000: Replace mdelay with usleep_range in peak_pci_probe Jia-Ju Bai
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