From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from va3outboundpool.messaging.microsoft.com (va3ehsobe010.messaging.microsoft.com [216.32.180.30]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "MSIT Machine Auth CA 2" (not verified)) by ozlabs.org (Postfix) with ESMTPS id EEFF82C0100 for ; Wed, 14 Aug 2013 16:40:20 +1000 (EST) From: Haijun Zhang To: , , Subject: [PATCH 1/3 V5] mmc:core: parse voltage from device-tree Date: Wed, 14 Aug 2013 13:46:11 +0800 Message-ID: <1376459171-21016-1-git-send-email-Haijun.Zhang@freescale.com> MIME-Version: 1.0 Content-Type: text/plain Cc: scottwood@freescale.com, cjb@laptop.org, Haijun Zhang , X.Xie@freescale.com, cbouatmailru@gmail.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Add function to support get voltage from device-tree. If there are voltage-range specified in device-tree node, this function will parse it and return the available voltage mask. Signed-off-by: Haijun Zhang --- changes for v5: - add binding spec for this device node changes for v4: - Add new parameter mask to return voltages. .../devicetree/bindings/mmc/fsl-esdhc.txt | 4 ++ drivers/mmc/core/core.c | 44 ++++++++++++++++++++++ include/linux/mmc/core.h | 2 + 3 files changed, 50 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/fsl-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-esdhc.txt index bd9be0b..b7943f3 100644 --- a/Documentation/devicetree/bindings/mmc/fsl-esdhc.txt +++ b/Documentation/devicetree/bindings/mmc/fsl-esdhc.txt @@ -19,6 +19,9 @@ Optional properties: "bus-width = <1>" property. - sdhci,auto-cmd12: specifies that a controller can only handle auto CMD12. + - voltage-ranges : two cells are required, first cell specifies minimum + slot voltage (mV), second cell specifies maximum slot voltage (mV). + Several ranges could be specified. Example: @@ -29,4 +32,5 @@ sdhci@2e000 { interrupt-parent = <&ipic>; /* Filled in by U-Boot */ clock-frequency = <0>; + voltage-ranges = <3300 3300>; }; diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 49a5bca..b9b9fb6 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -1196,6 +1197,49 @@ u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max) } EXPORT_SYMBOL(mmc_vddrange_to_ocrmask); +#ifdef CONFIG_OF + +/** + * mmc_of_parse_voltage - return mask of supported voltages + * @np: The device node need to be parsed. + * @mask: mask of voltages available for MMC/SD/SDIO + * + * 1. Return zero on success. + * 2. Return negative errno: voltage-range is invalid. + */ +int mmc_of_parse_voltage(struct device_node *np, u32 *mask) +{ + const u32 *voltage_ranges; + int num_ranges, i; + + voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges); + num_ranges = num_ranges / sizeof(*voltage_ranges) / 2; + if (!voltage_ranges || !num_ranges) { + pr_info("%s: voltage-ranges unspecified\n", np->full_name); + return -EINVAL; + } + + for (i = 0; i < num_ranges; i++) { + const int j = i * 2; + u32 ocr_mask; + + ocr_mask = mmc_vddrange_to_ocrmask( + be32_to_cpu(voltage_ranges[j]), + be32_to_cpu(voltage_ranges[j + 1])); + if (!ocr_mask) { + pr_err("%s: voltage-range #%d is invalid\n", + np->full_name, i); + return -EINVAL; + } + *mask |= ocr_mask; + } + + return 0; +} +EXPORT_SYMBOL(mmc_of_parse_voltage); + +#endif /* CONFIG_OF */ + #ifdef CONFIG_REGULATOR /** diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index 443243b..da51bec 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -208,6 +208,8 @@ static inline void mmc_claim_host(struct mmc_host *host) __mmc_claim_host(host, NULL); } +struct device_node; extern u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max); +extern int mmc_of_parse_voltage(struct device_node *np, u32 *mask); #endif /* LINUX_MMC_CORE_H */ -- 1.8.0