From 17ecd246414b3a0fe0cb248c86977a8bda465b7b Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Fri, 25 Aug 2017 09:42:02 +0200 Subject: [PATCH] rtc: sun6i: Add support for the external oscillator gate The RTC can output its 32kHz clock outside of the SoC, for example to clock a WiFi chip. Create a new clock that other devices will be able to retrieve, while maintaining the DT stability by providing a default name for that clock if clock-output-names doesn't list one. Signed-off-by: Maxime Ripard Signed-off-by: Alexandre Belloni --- .../devicetree/bindings/rtc/sun6i-rtc.txt | 4 ++-- drivers/rtc/rtc-sun6i.c | 24 +++++++++++++++++++--- 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt b/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt index 9459349..d5e26d3 100644 --- a/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt +++ b/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt @@ -10,7 +10,7 @@ Required properties: Required properties for new device trees - clocks : phandle to the 32kHz external oscillator -- clock-output-names : name of the LOSC clock created +- clock-output-names : names of the LOSC and its external output clocks created - #clock-cells : must be equals to 1. The RTC provides two clocks: the LOSC and its external output, with index 0 and 1 respectively. @@ -21,7 +21,7 @@ rtc: rtc@01f00000 { compatible = "allwinner,sun6i-a31-rtc"; reg = <0x01f00000 0x54>; interrupts = <0 40 4>, <0 41 4>; - clock-output-names = "osc32k"; + clock-output-names = "osc32k", "osc32k-out"; clocks = <&ext_osc32k>; #clock-cells = <1>; }; diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c index 305c4d0..3d2216c 100644 --- a/drivers/rtc/rtc-sun6i.c +++ b/drivers/rtc/rtc-sun6i.c @@ -73,6 +73,9 @@ #define SUN6I_ALARM_CONFIG 0x0050 #define SUN6I_ALARM_CONFIG_WAKEUP BIT(0) +#define SUN6I_LOSC_OUT_GATING 0x0060 +#define SUN6I_LOSC_OUT_GATING_EN BIT(0) + /* * Get date values */ @@ -125,6 +128,7 @@ struct sun6i_rtc_dev { struct clk_hw hw; struct clk_hw *int_osc; struct clk *losc; + struct clk *ext_losc; spinlock_t lock; }; @@ -188,13 +192,14 @@ static void __init sun6i_rtc_clk_init(struct device_node *node) struct clk_init_data init = { .ops = &sun6i_rtc_osc_ops, }; + const char *clkout_name = "osc32k-out"; const char *parents[2]; rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); if (!rtc) return; - clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws), + clk_data = kzalloc(sizeof(*clk_data) + (sizeof(*clk_data->hws) * 2), GFP_KERNEL); if (!clk_data) return; @@ -235,7 +240,8 @@ static void __init sun6i_rtc_clk_init(struct device_node *node) init.parent_names = parents; init.num_parents = of_clk_get_parent_count(node) + 1; - of_property_read_string(node, "clock-output-names", &init.name); + of_property_read_string_index(node, "clock-output-names", 0, + &init.name); rtc->losc = clk_register(NULL, &rtc->hw); if (IS_ERR(rtc->losc)) { @@ -243,8 +249,20 @@ static void __init sun6i_rtc_clk_init(struct device_node *node) return; } - clk_data->num = 1; + of_property_read_string_index(node, "clock-output-names", 1, + &clkout_name); + rtc->ext_losc = clk_register_gate(NULL, clkout_name, rtc->hw.init->name, + 0, rtc->base + SUN6I_LOSC_OUT_GATING, + SUN6I_LOSC_OUT_GATING_EN, 0, + &rtc->lock); + if (IS_ERR(rtc->ext_losc)) { + pr_crit("Couldn't register the LOSC external gate\n"); + return; + } + + clk_data->num = 2; clk_data->hws[0] = &rtc->hw; + clk_data->hws[1] = __clk_get_hw(rtc->ext_losc); of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data); return; -- 2.7.4