From 87c78d9512cb85c286de5a8941eaeda8ca6f7bac Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Mon, 12 Feb 2018 23:47:48 +0100 Subject: [PATCH] rtc: ds1742: use generic nvmem Instead of adding a binary sysfs attribute from the driver (which suffers from a race condition as the attribute appears after the device), use the core to register an nvmem device. Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-ds1742.c | 67 ++++++++++++++++------------------------ 1 file changed, 26 insertions(+), 41 deletions(-) diff --git a/drivers/rtc/rtc-ds1742.c b/drivers/rtc/rtc-ds1742.c index 84e19fe2ca3b..52baf925a690 100644 --- a/drivers/rtc/rtc-ds1742.c +++ b/drivers/rtc/rtc-ds1742.c @@ -53,9 +53,7 @@ struct rtc_plat_data { void __iomem *ioaddr_nvram; void __iomem *ioaddr_rtc; - size_t size_nvram; unsigned long last_jiffies; - struct bin_attribute nvram_attr; }; static int ds1742_rtc_set_time(struct device *dev, struct rtc_time *tm) @@ -122,34 +120,28 @@ static const struct rtc_class_ops ds1742_rtc_ops = { .set_time = ds1742_rtc_set_time, }; -static ssize_t ds1742_nvram_read(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t size) +static int ds1742_nvram_read(void *priv, unsigned int pos, void *val, + size_t bytes) { - struct device *dev = container_of(kobj, struct device, kobj); - struct platform_device *pdev = to_platform_device(dev); - struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + struct rtc_plat_data *pdata = priv; void __iomem *ioaddr = pdata->ioaddr_nvram; - ssize_t count; + u8 *buf = val; - for (count = 0; count < size; count++) + for (; bytes; bytes--) *buf++ = readb(ioaddr + pos++); - return count; + return 0; } -static ssize_t ds1742_nvram_write(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t size) +static int ds1742_nvram_write(void *priv, unsigned int pos, void *val, + size_t bytes) { - struct device *dev = container_of(kobj, struct device, kobj); - struct platform_device *pdev = to_platform_device(dev); - struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + struct rtc_plat_data *pdata = priv; void __iomem *ioaddr = pdata->ioaddr_nvram; - ssize_t count; + u8 *buf = val; - for (count = 0; count < size; count++) + for (; bytes; bytes--) writeb(*buf++, ioaddr + pos++); - return count; + return 0; } static int ds1742_rtc_probe(struct platform_device *pdev) @@ -160,6 +152,14 @@ static int ds1742_rtc_probe(struct platform_device *pdev) struct rtc_plat_data *pdata; void __iomem *ioaddr; int ret = 0; + struct nvmem_config nvmem_cfg = { + .name = "ds1742_nvram", + .word_size = 1, + .stride = 1, + .reg_read = ds1742_nvram_read, + .reg_write = ds1742_nvram_write, + }; + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) @@ -171,15 +171,10 @@ static int ds1742_rtc_probe(struct platform_device *pdev) return PTR_ERR(ioaddr); pdata->ioaddr_nvram = ioaddr; - pdata->size_nvram = resource_size(res) - RTC_SIZE; - pdata->ioaddr_rtc = ioaddr + pdata->size_nvram; + pdata->ioaddr_rtc = ioaddr + resource_size(res) - RTC_SIZE; - sysfs_bin_attr_init(&pdata->nvram_attr); - pdata->nvram_attr.attr.name = "nvram"; - pdata->nvram_attr.attr.mode = S_IRUGO | S_IWUSR; - pdata->nvram_attr.read = ds1742_nvram_read; - pdata->nvram_attr.write = ds1742_nvram_write; - pdata->nvram_attr.size = pdata->size_nvram; + nvmem_cfg.size = resource_size(res) - RTC_SIZE; + nvmem_cfg.priv = pdata; /* turn RTC on if it was not on */ ioaddr = pdata->ioaddr_rtc; @@ -202,24 +197,15 @@ static int ds1742_rtc_probe(struct platform_device *pdev) return PTR_ERR(rtc); rtc->ops = &ds1742_rtc_ops; + rtc->nvram_old_abi = true; ret = rtc_register_device(rtc); if (ret) return ret; - ret = sysfs_create_bin_file(&pdev->dev.kobj, &pdata->nvram_attr); - if (ret) - dev_err(&pdev->dev, "Unable to create sysfs entry: %s\n", - pdata->nvram_attr.attr.name); - - return 0; -} - -static int ds1742_rtc_remove(struct platform_device *pdev) -{ - struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + if (rtc_nvmem_register(rtc, &nvmem_cfg)) + dev_err(&pdev->dev, "Unable to register nvmem\n"); - sysfs_remove_bin_file(&pdev->dev.kobj, &pdata->nvram_attr); return 0; } @@ -231,7 +217,6 @@ MODULE_DEVICE_TABLE(of, ds1742_rtc_of_match); static struct platform_driver ds1742_rtc_driver = { .probe = ds1742_rtc_probe, - .remove = ds1742_rtc_remove, .driver = { .name = "rtc-ds1742", .of_match_table = of_match_ptr(ds1742_rtc_of_match), -- 2.20.1