On Tue, Apr 23, 2024 at 06:33:36PM +0800, Qiang Yu wrote:
> Some controllers may want to know the address of a certain doorbell. Hence
> add a new API where we read CHDBOFF register to get the base address of
> doorbell, so that the controller can calculate the address of the doorbell
> it wants by adding additional offset.
>
> Signed-off-by: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
One nitpick below. But I'll fix it.
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
> drivers/bus/mhi/host/init.c | 6 ++----
> drivers/bus/mhi/host/main.c | 16 ++++++++++++++++
> include/linux/mhi.h | 6 ++++++
> 3 files changed, 24 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
> index 7104c18..6e0fa79 100644
> --- a/drivers/bus/mhi/host/init.c
> +++ b/drivers/bus/mhi/host/init.c
> @@ -541,11 +541,9 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
> dev_dbg(dev, "Initializing MHI registers\n");
>
> /* Read channel db offset */
> - ret = mhi_read_reg(mhi_cntrl, base, CHDBOFF, &val);
> - if (ret) {
> - dev_err(dev, "Unable to read CHDBOFF register\n");
> + ret = mhi_get_channel_doorbell_offset(mhi_cntrl, &val);
> + if (ret)
> return -EIO;
return ret;
- Mani
> - }
>
> if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
> dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
> diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c
> index 15d657a..4de7567 100644
> --- a/drivers/bus/mhi/host/main.c
> +++ b/drivers/bus/mhi/host/main.c
> @@ -1691,3 +1691,19 @@ void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev)
> }
> }
> EXPORT_SYMBOL_GPL(mhi_unprepare_from_transfer);
> +
> +int mhi_get_channel_doorbell_offset(struct mhi_controller *mhi_cntrl, u32 *chdb_offset)
> +{
> + struct device *dev = &mhi_cntrl->mhi_dev->dev;
> + void __iomem *base = mhi_cntrl->regs;
> + int ret;
> +
> + ret = mhi_read_reg(mhi_cntrl, base, CHDBOFF, chdb_offset);
> + if (ret) {
> + dev_err(dev, "Unable to read CHDBOFF register\n");
> + return -EIO;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(mhi_get_channel_doorbell_offset);
> diff --git a/include/linux/mhi.h b/include/linux/mhi.h
> index d968e1a..cb3b676 100644
> --- a/include/linux/mhi.h
> +++ b/include/linux/mhi.h
> @@ -816,4 +816,10 @@ int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
> */
> bool mhi_queue_is_full(struct mhi_device *mhi_dev, enum dma_data_direction dir);
>
> +/**
> + * mhi_get_channel_doorbell_offset - Get the channel doorbell offset
> + * @mhi_cntrl: MHI controller
> + * @chdb_offset: Channel doorbell offset
> + */
> +int mhi_get_channel_doorbell_offset(struct mhi_controller *mhi_cntrl, u32 *chdb_offset);
> #endif /* _MHI_H_ */
> --
> 2.7.4
>
>
--
மணிவண்ணன் சதாசிவம்
