From: Xinming Hu <huxm@xxxxxxxxxxx> sdio device drivers need be able to get the host supported max_segs and max_seg_size, so that they know the buffer size to allocate while utilizing the scatter/gather DMA buffer list. This patch provides API for this purpose. Signed-off-by: Xinming Hu <huxm@xxxxxxxxxxx> Signed-off-by: Amitkumar Karwar <akarwar@xxxxxxxxxxx> --- v2: v2 was submitted with minor improvement like replacing BUG_ON() with WARN_ON() v3: Addressed below review comments from Ulf Hansson a) In v3, patch has been split into two separate patches. b) Patch 1/2 introduces an API to fetch max_seg_size and max_segs c) Replaced WARN_ON() with proper error code when sg_ptr->length is invalid d) Instead of duplicating the code in mmc_io_rw_extended(), extra bool parameter has been added to this function and used it in new APIs for SG. --- drivers/mmc/core/sdio_io.c | 27 ++++++++++++++++++++++ .../wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 6 ++--- include/linux/mmc/sdio_func.h | 3 +++ 3 files changed, 33 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c index 78cb4d5..a546c89 100644 --- a/drivers/mmc/core/sdio_io.c +++ b/drivers/mmc/core/sdio_io.c @@ -720,3 +720,30 @@ int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags) return 0; } EXPORT_SYMBOL_GPL(sdio_set_host_pm_flags); + +/** + * sdio_get_host_max_seg_size - get host maximum segment size + * @func: SDIO function attached to host + */ +unsigned int sdio_get_host_max_seg_size(struct sdio_func *func) +{ + WARN_ON(!func); + WARN_ON(!func->card); + + return func->card->host->max_seg_size; +} +EXPORT_SYMBOL_GPL(sdio_get_host_max_seg_size); + +/** + * sdio_get_host_max_seg_count - get host maximum segment count + * @func: SDIO function attached to host + */ +unsigned short sdio_get_host_max_seg_count(struct sdio_func *func) +{ + WARN_ON(!func); + WARN_ON(!func->card); + + return func->card->host->max_segs; +} +EXPORT_SYMBOL_GPL(sdio_get_host_max_seg_count); + diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c index c4b89d2..ba579f4 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c @@ -896,9 +896,9 @@ void brcmf_sdiod_sgtable_alloc(struct brcmf_sdio_dev *sdiodev) max_blocks = min_t(uint, host->max_blk_count, 511u); sdiodev->max_request_size = min_t(uint, host->max_req_size, max_blocks * func->cur_blksize); - sdiodev->max_segment_count = min_t(uint, host->max_segs, - SG_MAX_SINGLE_ALLOC); - sdiodev->max_segment_size = host->max_seg_size; + sdiodev->max_segment_count = min_t(uint, SG_MAX_SINGLE_ALLOC, + sdio_get_host_max_seg_count(func)); + sdiodev->max_segment_size = sdio_get_host_max_seg_size(func); if (!sdiodev->sg_support) return; diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h index aab032a..b2b91df 100644 --- a/include/linux/mmc/sdio_func.h +++ b/include/linux/mmc/sdio_func.h @@ -159,4 +159,7 @@ extern void sdio_f0_writeb(struct sdio_func *func, unsigned char b, extern mmc_pm_flag_t sdio_get_host_pm_caps(struct sdio_func *func); extern int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags); +unsigned short sdio_get_host_max_seg_count(struct sdio_func *func); +unsigned int sdio_get_host_max_seg_size(struct sdio_func *func); + #endif /* LINUX_MMC_SDIO_FUNC_H */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html