Commit 1a42aef2 authored by Bhaumik Bhatt's avatar Bhaumik Bhatt Committed by Manivannan Sadhasivam
Browse files

bus: mhi: core: Introduce internal register poll helper function 



Introduce helper function to allow MHI core driver to poll for
a value in a register field. This helps reach a common path to
read and poll register values along with a retry time interval.

Signed-off-by: default avatarBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: default avatarLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1617215665-19593-2-git-send-email-bbhatt@codeaurora.org


Signed-off-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
parent 19e60d6e

drivers/bus/mhi/core/internal.h

+3 −0
Original line number Diff line number Diff line
@@ -646,6 +646,9 @@ int __must_check mhi_read_reg(struct mhi_controller *mhi_cntrl, 
int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl,

				    void __iomem *base, u32 offset, u32 mask,

				    u32 shift, u32 *out);

int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,

				    void __iomem *base, u32 offset, u32 mask,

				    u32 shift, u32 val, u32 delayus);

void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,

		   u32 offset, u32 val);

void mhi_write_reg_field(struct mhi_controller *mhi_cntrl, void __iomem *base,

drivers/bus/mhi/core/main.c

+23 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
 *

 */



#include <linux/delay.h>

#include <linux/device.h>

#include <linux/dma-direction.h>

#include <linux/dma-mapping.h>
@@ -37,6 +38,28 @@ int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl, 
	return 0;

}



int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,

				    void __iomem *base, u32 offset,

				    u32 mask, u32 shift, u32 val, u32 delayus)

{

	int ret;

	u32 out, retry = (mhi_cntrl->timeout_ms * 1000) / delayus;



	while (retry--) {

		ret = mhi_read_reg_field(mhi_cntrl, base, offset, mask, shift,

					 &out);

		if (ret)

			return ret;



		if (out == val)

			return 0;



		fsleep(delayus);

	}



	return -ETIMEDOUT;

}



void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,

		   u32 offset, u32 val)

{