From: Guodong Xu <guodong.xu@linaro.org> To: heiko@sntech.de, shawn.lin@rock-chips.com, jh80.chung@samsung.com, robh+dt@kernel.org, mark.rutland@arm.com, ulf.hansson@linaro.org, guodong.xu@linaro.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mmc@vger.kernel.org, Xinwei Kong <kong.kongxinwei@hisilicon.com>, Zhangfei Gao <zhangfei.gao@linaro.org> Subject: [PATCH v5 2/2] mmc: dw_mmc: add reset support to dwmmc host controller Date: Fri, 12 Aug 2016 16:51:26 +0800 [thread overview] Message-ID: <1470991886-22412-3-git-send-email-guodong.xu@linaro.org> (raw) In-Reply-To: <1470991886-22412-1-git-send-email-guodong.xu@linaro.org> Dwmmc host controller may in unknown state when entering kernel boot. One example is when booting from eMMC, bootloader need initialize MMC host controller into some state so it can read. In order to make sure MMC host controller in a clean initial state, this reset support is added. With this patch, a 'resets' property can be added into dw_mmc device tree node. The hardware logic is: dwmmc host controller IP receives a reset signal from a 'reset provider' (eg. power management unit). The 'resets' property points to this reset signal. So, during dwmmc driver probe, it can use this signal to reset itself. Refer to [1] for more information. [1] Documentation/devicetree/bindings/reset/reset.txt Signed-off-by: Guodong Xu <guodong.xu@linaro.org> Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com> --- drivers/mmc/host/dw_mmc.c | 23 ++++++++++++++++++++++- include/linux/mmc/dw_mmc.h | 2 ++ 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 1b719a6..4dff0ee 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2872,6 +2872,13 @@ static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host) if (!pdata) return ERR_PTR(-ENOMEM); + /* find reset controller when exist */ + pdata->rstc = devm_reset_control_get_optional(dev, NULL); + if (IS_ERR(pdata->rstc)) { + if (PTR_ERR(pdata->rstc) == -EPROBE_DEFER) + return ERR_PTR(-EPROBE_DEFER); + } + /* find out number of slots supported */ of_property_read_u32(np, "num-slots", &pdata->num_slots); @@ -2943,7 +2950,9 @@ int dw_mci_probe(struct dw_mci *host) if (!host->pdata) { host->pdata = dw_mci_parse_dt(host); - if (IS_ERR(host->pdata)) { + if (PTR_ERR(host->pdata) == -EPROBE_DEFER) { + return -EPROBE_DEFER; + } else if (IS_ERR(host->pdata)) { dev_err(host->dev, "platform data not available\n"); return -EINVAL; } @@ -2997,6 +3006,12 @@ int dw_mci_probe(struct dw_mci *host) } } + if (!IS_ERR(host->pdata->rstc)) { + reset_control_assert(host->pdata->rstc); + usleep_range(10, 50); + reset_control_deassert(host->pdata->rstc); + } + setup_timer(&host->cmd11_timer, dw_mci_cmd11_timer, (unsigned long)host); @@ -3146,6 +3161,9 @@ err_dmaunmap: if (host->use_dma && host->dma_ops->exit) host->dma_ops->exit(host); + if (!IS_ERR(host->pdata->rstc)) + reset_control_assert(host->pdata->rstc); + err_clk_ciu: clk_disable_unprepare(host->ciu_clk); @@ -3176,6 +3194,9 @@ void dw_mci_remove(struct dw_mci *host) if (host->use_dma && host->dma_ops->exit) host->dma_ops->exit(host); + if (!IS_ERR(host->pdata->rstc)) + reset_control_assert(host->pdata->rstc); + clk_disable_unprepare(host->ciu_clk); clk_disable_unprepare(host->biu_clk); } diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h index 83b0edfc..f5af2bd 100644 --- a/include/linux/mmc/dw_mmc.h +++ b/include/linux/mmc/dw_mmc.h @@ -17,6 +17,7 @@ #include <linux/scatterlist.h> #include <linux/mmc/core.h> #include <linux/dmaengine.h> +#include <linux/reset.h> #define MAX_MCI_SLOTS 2 @@ -259,6 +260,7 @@ struct dw_mci_board { /* delay in mS before detecting cards after interrupt */ u32 detect_delay_ms; + struct reset_control *rstc; struct dw_mci_dma_ops *dma_ops; struct dma_pdata *data; }; -- 1.9.1
WARNING: multiple messages have this Message-ID (diff)
From: guodong.xu@linaro.org (Guodong Xu) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v5 2/2] mmc: dw_mmc: add reset support to dwmmc host controller Date: Fri, 12 Aug 2016 16:51:26 +0800 [thread overview] Message-ID: <1470991886-22412-3-git-send-email-guodong.xu@linaro.org> (raw) In-Reply-To: <1470991886-22412-1-git-send-email-guodong.xu@linaro.org> Dwmmc host controller may in unknown state when entering kernel boot. One example is when booting from eMMC, bootloader need initialize MMC host controller into some state so it can read. In order to make sure MMC host controller in a clean initial state, this reset support is added. With this patch, a 'resets' property can be added into dw_mmc device tree node. The hardware logic is: dwmmc host controller IP receives a reset signal from a 'reset provider' (eg. power management unit). The 'resets' property points to this reset signal. So, during dwmmc driver probe, it can use this signal to reset itself. Refer to [1] for more information. [1] Documentation/devicetree/bindings/reset/reset.txt Signed-off-by: Guodong Xu <guodong.xu@linaro.org> Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com> --- drivers/mmc/host/dw_mmc.c | 23 ++++++++++++++++++++++- include/linux/mmc/dw_mmc.h | 2 ++ 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 1b719a6..4dff0ee 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2872,6 +2872,13 @@ static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host) if (!pdata) return ERR_PTR(-ENOMEM); + /* find reset controller when exist */ + pdata->rstc = devm_reset_control_get_optional(dev, NULL); + if (IS_ERR(pdata->rstc)) { + if (PTR_ERR(pdata->rstc) == -EPROBE_DEFER) + return ERR_PTR(-EPROBE_DEFER); + } + /* find out number of slots supported */ of_property_read_u32(np, "num-slots", &pdata->num_slots); @@ -2943,7 +2950,9 @@ int dw_mci_probe(struct dw_mci *host) if (!host->pdata) { host->pdata = dw_mci_parse_dt(host); - if (IS_ERR(host->pdata)) { + if (PTR_ERR(host->pdata) == -EPROBE_DEFER) { + return -EPROBE_DEFER; + } else if (IS_ERR(host->pdata)) { dev_err(host->dev, "platform data not available\n"); return -EINVAL; } @@ -2997,6 +3006,12 @@ int dw_mci_probe(struct dw_mci *host) } } + if (!IS_ERR(host->pdata->rstc)) { + reset_control_assert(host->pdata->rstc); + usleep_range(10, 50); + reset_control_deassert(host->pdata->rstc); + } + setup_timer(&host->cmd11_timer, dw_mci_cmd11_timer, (unsigned long)host); @@ -3146,6 +3161,9 @@ err_dmaunmap: if (host->use_dma && host->dma_ops->exit) host->dma_ops->exit(host); + if (!IS_ERR(host->pdata->rstc)) + reset_control_assert(host->pdata->rstc); + err_clk_ciu: clk_disable_unprepare(host->ciu_clk); @@ -3176,6 +3194,9 @@ void dw_mci_remove(struct dw_mci *host) if (host->use_dma && host->dma_ops->exit) host->dma_ops->exit(host); + if (!IS_ERR(host->pdata->rstc)) + reset_control_assert(host->pdata->rstc); + clk_disable_unprepare(host->ciu_clk); clk_disable_unprepare(host->biu_clk); } diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h index 83b0edfc..f5af2bd 100644 --- a/include/linux/mmc/dw_mmc.h +++ b/include/linux/mmc/dw_mmc.h @@ -17,6 +17,7 @@ #include <linux/scatterlist.h> #include <linux/mmc/core.h> #include <linux/dmaengine.h> +#include <linux/reset.h> #define MAX_MCI_SLOTS 2 @@ -259,6 +260,7 @@ struct dw_mci_board { /* delay in mS before detecting cards after interrupt */ u32 detect_delay_ms; + struct reset_control *rstc; struct dw_mci_dma_ops *dma_ops; struct dma_pdata *data; }; -- 1.9.1
next prev parent reply other threads:[~2016-08-12 8:51 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top [not found] <CGME20160812085218epcas1p34d84a42a931dcc09fe7a77be59065499@epcas1p3.samsung.com> 2016-08-12 8:51 ` [PATCH v5 0/2] mmc: dw_mmc: host controller reset support Guodong Xu 2016-08-12 8:51 ` Guodong Xu 2016-08-12 8:51 ` Guodong Xu 2016-08-12 8:51 ` [PATCH v5 1/2] Documentation: synopsys-dw-mshc: add binding for resets Guodong Xu 2016-08-12 8:51 ` Guodong Xu 2016-08-12 8:51 ` Guodong Xu 2016-08-12 8:51 ` Guodong Xu [this message] 2016-08-12 8:51 ` [PATCH v5 2/2] mmc: dw_mmc: add reset support to dwmmc host controller Guodong Xu 2016-08-12 9:19 ` [PATCH v5 0/2] mmc: dw_mmc: host controller reset support Jaehoon Chung 2016-08-12 9:19 ` Jaehoon Chung
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1470991886-22412-3-git-send-email-guodong.xu@linaro.org \ --to=guodong.xu@linaro.org \ --cc=devicetree@vger.kernel.org \ --cc=heiko@sntech.de \ --cc=jh80.chung@samsung.com \ --cc=kong.kongxinwei@hisilicon.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mmc@vger.kernel.org \ --cc=mark.rutland@arm.com \ --cc=robh+dt@kernel.org \ --cc=shawn.lin@rock-chips.com \ --cc=ulf.hansson@linaro.org \ --cc=zhangfei.gao@linaro.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.