From 7130856f56054a031c492d37896cbcbfd04a61b5 Mon Sep 17 00:00:00 2001 From: Ladislav Michl Date: Sat, 28 May 2022 19:36:13 +0200 Subject: [PATCH] rtc: twl: add NVRAM support Export SRAM using nvmem. Signed-off-by: Ladislav Michl Reviewed-by: Tony Lindgren Link: https://lore.kernel.org/r/ZDf7qZTiml0ijD2g@lenoch Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-twl.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/rtc/rtc-twl.c b/drivers/rtc/rtc-twl.c index 81b36948c2fa..f8f0d774a06e 100644 --- a/drivers/rtc/rtc-twl.c +++ b/drivers/rtc/rtc-twl.c @@ -487,11 +487,24 @@ static const struct rtc_class_ops twl_rtc_ops = { .alarm_irq_enable = twl_rtc_alarm_irq_enable, }; +static int twl_nvram_read(void *priv, unsigned int offset, void *val, + size_t bytes) +{ + return twl_i2c_read((long)priv, val, offset, bytes); +} + +static int twl_nvram_write(void *priv, unsigned int offset, void *val, + size_t bytes) +{ + return twl_i2c_write((long)priv, val, offset, bytes); +} + /*----------------------------------------------------------------------*/ static int twl_rtc_probe(struct platform_device *pdev) { struct twl_rtc *twl_rtc; + struct nvmem_config nvmem_cfg; struct device_node *np = pdev->dev.of_node; int ret = -EINVAL; int irq = platform_get_irq(pdev, 0); @@ -579,6 +592,30 @@ static int twl_rtc_probe(struct platform_device *pdev) return ret; } + memset(&nvmem_cfg, 0, sizeof(nvmem_cfg)); + nvmem_cfg.name = "twl-secured-"; + nvmem_cfg.type = NVMEM_TYPE_BATTERY_BACKED; + nvmem_cfg.reg_read = twl_nvram_read, + nvmem_cfg.reg_write = twl_nvram_write, + nvmem_cfg.word_size = 1; + nvmem_cfg.stride = 1; + if (twl_class_is_4030()) { + /* 20 bytes SECURED_REG area */ + nvmem_cfg.size = 20; + nvmem_cfg.priv = (void *)TWL_MODULE_SECURED_REG; + devm_rtc_nvmem_register(twl_rtc->rtc, &nvmem_cfg); + /* 8 bytes BACKUP area */ + nvmem_cfg.name = "twl-backup-"; + nvmem_cfg.size = 8; + nvmem_cfg.priv = (void *)TWL4030_MODULE_BACKUP; + devm_rtc_nvmem_register(twl_rtc->rtc, &nvmem_cfg); + } else { + /* 8 bytes SECURED_REG area */ + nvmem_cfg.size = 8; + nvmem_cfg.priv = (void *)TWL_MODULE_SECURED_REG; + devm_rtc_nvmem_register(twl_rtc->rtc, &nvmem_cfg); + } + return 0; }