Re: [PATCH mmc-next v3 2/3] mmc: sdhci: introduce adma_write_desc() hook to struct sdhci_ops

From: Adrian Hunter
Date: Wed Aug 15 2018 - 10:08:57 EST


On 30/07/18 05:45, Jisheng Zhang wrote:
> Add this hook so that it can be overridden with driver specific
> implementations. We also rename the original sdhci_adma_write_desc()
> to _sdhci_adma_write_desc() and export it, so that it could be reused
> by driver's specific implementations.
>
> Signed-off-by: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci.c | 31 +++++++++++++++++++++++--------
> drivers/mmc/host/sdhci.h | 6 ++++++
> 2 files changed, 29 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 14dd4a49e03b..50c846d99182 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -554,8 +554,8 @@ static void sdhci_kunmap_atomic(void *buffer, unsigned long *flags)
> local_irq_restore(*flags);
> }
>
> -static void sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
> - dma_addr_t addr, int len, unsigned cmd)
> +unsigned int _sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
> + dma_addr_t addr, int len, unsigned int cmd)
> {
> struct sdhci_adma2_64_desc *dma_desc = desc;
>
> @@ -566,6 +566,19 @@ static void sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
>
> if (host->flags & SDHCI_USE_64_BIT_DMA)
> dma_desc->addr_hi = cpu_to_le32((u64)addr >> 32);
> +
> + return host->desc_sz;
> +}
> +EXPORT_SYMBOL_GPL(_sdhci_adma_write_desc);

Let's make the exported name without the _ i.e.sdhci_adma_write_desc

> +
> +static unsigned int sdhci_adma_write_desc(struct sdhci_host *host, void *desc,

Let's inline this and use __ i.e.

static inline void __sdhci_adma_write_desc(struct sdhci_host *host,

> + dma_addr_t addr, int len,
> + unsigned int cmd)
> +{
> + if (host->ops->adma_write_desc)
> + return host->ops->adma_write_desc(host, desc, addr, len, cmd);
> +
> + return _sdhci_adma_write_desc(host, desc, addr, len, cmd);
> }
>
> static void sdhci_adma_mark_end(void *desc)
> @@ -585,6 +598,7 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
> void *desc, *align;
> char *buffer;
> int len, offset, i;
> + unsigned int desc_sz;
>
> /*
> * The spec does not specify endianness of descriptor table.
> @@ -618,15 +632,16 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
> }
>
> /* tran, valid */
> - sdhci_adma_write_desc(host, desc, align_addr, offset,
> - ADMA2_TRAN_VALID);
> + desc_sz = sdhci_adma_write_desc(host, desc,

Instead of returning desc_sz, might just as well pass &desc and have the
function set its new value.

> + align_addr, offset,
> + ADMA2_TRAN_VALID);
>
> BUG_ON(offset > 65536);
>
> align += SDHCI_ADMA2_ALIGN;
> align_addr += SDHCI_ADMA2_ALIGN;
>
> - desc += host->desc_sz;
> + desc += desc_sz;
>
> addr += offset;
> len -= offset;
> @@ -636,9 +651,9 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
>
> if (len) {
> /* tran, valid */
> - sdhci_adma_write_desc(host, desc, addr, len,
> - ADMA2_TRAN_VALID);
> - desc += host->desc_sz;
> + desc_sz = sdhci_adma_write_desc(host, desc, addr, len,
> + ADMA2_TRAN_VALID);
> + desc += desc_sz;
> }
>
> /*
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index d55fd7033e93..0aad0ee8f63b 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -605,6 +605,9 @@ struct sdhci_ops {
> void (*adma_workaround)(struct sdhci_host *host, u32 intmask);
> void (*card_event)(struct sdhci_host *host);
> void (*voltage_switch)(struct sdhci_host *host);
> + unsigned int (*adma_write_desc)(struct sdhci_host *host, void *desc,
> + dma_addr_t addr, int len,
> + unsigned int cmd);
> };
>
> #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
> @@ -735,6 +738,9 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
> int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
> struct mmc_ios *ios);
> void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable);
> +unsigned int _sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
> + dma_addr_t addr, int len,
> + unsigned int cmd);
>
> #ifdef CONFIG_PM
> int sdhci_suspend_host(struct sdhci_host *host);
>