Re: [PATCH v4 2/2] power: reset: at91-shdwc: add new shutdown controller driver
From: Nicolas Ferre <hidden>
Date: 2016-03-16 11:36:52
Also in:
linux-arm-kernel, lkml
Le 14/03/2016 21:22, Alexandre Belloni a écrit :
On 10/03/2016 at 16:37:40 +0100, Nicolas Ferre wrote :quoted
+ATMEL AT91 Alternative Shutdown ControllerCan't that be sama5d2 instead of alternative?quoted
+M: Nicolas Ferre [off-list ref] +S: Supported +F: drivers/power/reset/at91-shdwc.cI would also use that in the filename. Because once there is a third shdwc, I'm not sure how you will be able to name it.quoted
+config POWER_RESET_AT91_SHDWCI would also include that in the config name.quoted
+ tristate "Atmel AT91 shutdown controller driver" + depends on ARCH_AT91 || COMPILE_TEST + default SOC_SAMA5 + help + This driver supports the alternate shutdown controller for some Atmel + SAMA5 SoCs. It is present for example on SAMA5D2 SoC. +quoted
+#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/printk.h> + +#define SLOW_CLOCK_FREQ 32768 + +#define AT91_SHDW_CR 0x00 /* Shut Down Control Register */ +#define AT91_SHDW_SHDW BIT(0) /* Shut Down command */ +#define AT91_SHDW_KEY (0xa5UL << 24) /* KEY Password */ + +#define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */ +#define AT91_SHDW_WKUPDBC_SHIFT 24 +#define AT91_SHDW_WKUPDBC_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPDBC(x) (((x) << AT91_SHDW_WKUPDBC_SHIFT) \ + & AT91_SHDW_WKUPDBC_MASK) + +#define AT91_SHDW_SR 0x08 /* Shut Down Status Register */ +#define AT91_SHDW_WKUPIS_SHIFT 16 +#define AT91_SHDW_WKUPIS_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPIS(x) ((1 << (x)) << AT91_SHDW_WKUPIS_SHIFT \ + & AT91_SHDW_WKUPIS_MASK) + +#define AT91_SHDW_WUIR 0x0c /* Shutdown Wake-up Inputs Register */ +#define AT91_SHDW_WKUPEN_MASK GENMASK(15, 0) +#define AT91_SHDW_WKUPEN(x) ((1 << (x)) & AT91_SHDW_WKUPEN_MASK) +#define AT91_SHDW_WKUPT_SHIFT 16 +#define AT91_SHDW_WKUPT_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPT(x) ((1 << (x)) << AT91_SHDW_WKUPT_SHIFT \ + & AT91_SHDW_WKUPT_MASK) + +#define SHDW_WK_PIN(reg, cfg) ((reg) & AT91_SHDW_WKUPIS((cfg)->wkup_pin_input)) +#define SHDW_RTCWK(reg, cfg) (((reg) >> ((cfg)->sr_rtcwk_shift)) & 0x1) +#define SHDW_RTCWKEN(cfg) (1 << ((cfg)->mr_rtcwk_shift)) + +#define DBC_PERIOD_US(x) DIV_ROUND_UP_ULL((1000000 * (x)), \ + SLOW_CLOCK_FREQ) + +struct shdwc_config { + u8 wkup_pin_input; + u8 mr_rtcwk_shift; + u8 sr_rtcwk_shift; +}; + +struct shdwc { + struct shdwc_config *cfg; + void __iomem *at91_shdwc_base; +}; + +/* + * Hold configuration here, cannot be more than one instance of the driver + * since pm_power_off itself is global. + */ +static struct shdwc *at91_shdwc; +static struct clk *sclk; + +static const unsigned long long sdwc_dbc_period[] = { + 0, 3, 32, 512, 4096, 32768, +}; + +static void __init at91_wakeup_status(struct platform_device *pdev) +{ + struct shdwc *shdw = platform_get_drvdata(pdev); + u32 reg; + char *reason = "unknown"; + + reg = readl(shdw->at91_shdwc_base + AT91_SHDW_SR); + + dev_dbg(&pdev->dev, "%s: status = %#x\n", __func__, reg); + + /* Simple power-on, just bail out */ + if (!reg) + return; + + if (SHDW_WK_PIN(reg, shdw->cfg)) + reason = "WKUP pin"; + else if (SHDW_RTCWK(reg, shdw->cfg)) + reason = "RTC"; + + pr_info("AT91: Wake-Up source: %s\n", reason); +} + +static void at91_poweroff(void) +{ + writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, + at91_shdwc->at91_shdwc_base + AT91_SHDW_CR);This is still not properly aligned :)
Ok for this one.
quoted
+} + +static u32 at91_shdwc_debouncer_value(struct platform_device *pdev, + u32 in_period_us) +{ + int i; + int max_idx = ARRAY_SIZE(sdwc_dbc_period) - 1; + unsigned long long period_us; + unsigned long long max_period_us = DBC_PERIOD_US(sdwc_dbc_period[max_idx]); + + if (in_period_us > max_period_us) { + dev_warn(&pdev->dev, + "debouncer period %u too big, reduced to %llu us\n", + in_period_us, max_period_us); + return max_idx; + } + + for (i = max_idx - 1; i > 0; i--) { + period_us = DBC_PERIOD_US(sdwc_dbc_period[i]); + dev_dbg(&pdev->dev, "%s: ref[%d] = %llu\n", + __func__, i, period_us);Alignment is not correct.quoted
+ if (in_period_us > period_us) + break; + } + + return i + 1; +} + +static u32 at91_shdwc_get_wakeup_input(struct platform_device *pdev, + struct device_node *np) +{ + struct device_node *cnp; + u32 wk_input_mask; + u32 wuir = 0; + u32 wk_input; + + for_each_child_of_node(np, cnp) { + if (of_property_read_u32(cnp, "reg", &wk_input)) { + dev_warn(&pdev->dev, "reg property is missing for %s\n", + cnp->full_name); + continue; + } + + wk_input_mask = 1 << wk_input; + if (!(wk_input_mask & AT91_SHDW_WKUPEN_MASK)) { + dev_warn(&pdev->dev, + "wake-up input %d out of bounds ignore\n", + wk_input); + continue; + } + wuir |= wk_input_mask; + + if (of_property_read_bool(cnp, "atmel,wakeup-active-high")) + wuir |= AT91_SHDW_WKUPT(wk_input); + + dev_dbg(&pdev->dev, "%s: (child %d) wuir = %#x\n", + __func__, wk_input, wuir);Alignment is not correct
I don't agree with you on the 2 last ones. In Documentation/CodingStyle, it is said that: "Chapter 2: Breaking long lines and strings [..] Descendants are always substantially shorter than the parent and are placed substantially to the right." Together with the 80 column requirement that I also fulfil, I think that my code is well aligned. So I keep it like this ;-) Bye, -- Nicolas Ferre -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html