From patchwork Fri Oct 16 07:59:29 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiko Schocher X-Patchwork-Id: 531081 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 231F31402B2 for ; Fri, 16 Oct 2015 18:59:38 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752042AbbJPH7h (ORCPT ); Fri, 16 Oct 2015 03:59:37 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:51661 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750756AbbJPH7g (ORCPT ); Fri, 16 Oct 2015 03:59:36 -0400 Received: from frontend02.mail.m-online.net (unknown [192.168.8.183]) by mail-out.m-online.net (Postfix) with ESMTP id 3ncfyY1SB4z3hpNR; Fri, 16 Oct 2015 09:59:33 +0200 (CEST) Received: from localhost (dynscan2.mnet-online.de [192.168.6.69]) by mail.m-online.net (Postfix) with ESMTP id 3ncfyY0gVdzvdWt; Fri, 16 Oct 2015 09:59:33 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.184]) by localhost (dynscan2.mail.m-online.net [192.168.6.69]) (amavisd-new, port 10024) with ESMTP id Ab2yQV2gue4r; Fri, 16 Oct 2015 09:59:31 +0200 (CEST) X-Auth-Info: KwOSOz3NZgi/7IIAWm/Dg8D7Ue9sj2EDzDqxjaL2yRk= Received: from mail-internal.denx.de (host-82-135-33-74.customer.m-online.net [82.135.33.74]) by smtp-auth.mnet-online.de (Postfix) with ESMTPA; Fri, 16 Oct 2015 09:59:31 +0200 (CEST) Received: from pollux.denx.de (pollux [192.168.1.1]) by mail-internal.denx.de (Postfix) with ESMTP id 6ABD83438F3; Fri, 16 Oct 2015 09:59:31 +0200 (CEST) Received: by pollux.denx.de (Postfix, from userid 515) id E3EB36C02; Fri, 16 Oct 2015 09:59:30 +0200 (CEST) From: Heiko Schocher To: linux-kernel@vger.kernel.org Cc: Heiko Schocher , Alexandre Belloni , Georg.Soffel@bosch-si.com, rtc-linux@googlegroups.com, Alessandro Zummo , devicetree@vger.kernel.org Subject: [PATCH v2] rtc: pcf8563: add CLKOUT to common clock framework Date: Fri, 16 Oct 2015 09:59:29 +0200 Message-Id: <1444982369-26046-1-git-send-email-hs@denx.de> X-Mailer: git-send-email 2.1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Add the clkout output clk to the common clock framework. Disable the CLKOUT of the RTC after power-up. After power-up/reset of the RTC, CLKOUT is enabled by default, with CLKOUT enabled the RTC chip has 2-3 times higher power consumption. Signed-off-by: Heiko Schocher --- Changes in v2: - add comments from Alexandre Belloni - remove the DT property, instead register for the CLKOUT a clk in the common clk framework. The clk is disabled by default. Documentation/devicetree/bindings/rtc/pcf8563.txt | 28 ++++ drivers/rtc/rtc-pcf8563.c | 164 +++++++++++++++++++++- 2 files changed, 191 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/rtc/pcf8563.txt diff --git a/Documentation/devicetree/bindings/rtc/pcf8563.txt b/Documentation/devicetree/bindings/rtc/pcf8563.txt new file mode 100644 index 0000000..cdb81ef --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/pcf8563.txt @@ -0,0 +1,28 @@ +* Philips PCF8563/Epson RTC8564 Real Time Clock + +Philips PCF8563/Epson RTC8564 Real Time Clock + +Required properties: +see: Documentation/devicetree/bindings/i2c/trivial-devices.txt + +Optional property: +- #clock-cells: Should be 1. +- clocks: Reference to the clock entry. +- clock-output-names: + overwrite the default clock name "pcf8563-clkout" + +Example: + +rtcclk: rtcclk { + compatible = "fixed-clock"; + #clock-cells = <1>; + clock-frequency = <1>; + clock-output-names = "rtcclk"; +}; + +pcf8563@51 { + compatible = "nxp,pcf8563"; + reg = <0x51>; + #clock-cells = <1>; + clocks = <&rtcclk 0>; +}; diff --git a/drivers/rtc/rtc-pcf8563.c b/drivers/rtc/rtc-pcf8563.c index e569243..0c2f85f 100644 --- a/drivers/rtc/rtc-pcf8563.c +++ b/drivers/rtc/rtc-pcf8563.c @@ -14,6 +14,7 @@ * published by the Free Software Foundation. */ +#include #include #include #include @@ -40,7 +41,14 @@ #define PCF8563_REG_AMN 0x09 /* alarm */ -#define PCF8563_REG_CLKO 0x0D /* clock out */ +#define PCF8563_REG_CLKO 0x0D /* clock out */ +#define PCF8563_REG_CLKO_FE 0x80 /* clock out enabled */ +#define PCF8563_REG_CLKO_F_MASK 0x03 /* frequenc mask */ +#define PCF8563_REG_CLKO_F_32768HZ 0x00 +#define PCF8563_REG_CLKO_F_1024HZ 0x01 +#define PCF8563_REG_CLKO_F_32HZ 0x02 +#define PCF8563_REG_CLKO_F_1HZ 0x03 + #define PCF8563_REG_TMRC 0x0E /* timer control */ #define PCF8563_TMRC_ENABLE BIT(7) #define PCF8563_TMRC_4096 0 @@ -76,6 +84,7 @@ struct pcf8563 { int voltage_low; /* incicates if a low_voltage was detected */ struct i2c_client *client; + struct clk_hw clkout_hw; }; static int pcf8563_read_block_data(struct i2c_client *client, unsigned char reg, @@ -390,6 +399,156 @@ static int pcf8563_irq_enable(struct device *dev, unsigned int enabled) return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled); } +/* + * Handling of the clkout + */ + +#define clkout_hw_to_pcf8563(_hw) container_of(_hw, struct pcf8563, clkout_hw) + +static int clkout_rates[] = { + 32768, + 1024, + 32, + 1, +}; + +static unsigned long pcf8563_clkout_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); + struct i2c_client *client = pcf8563->client; + unsigned char buf; + int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); + + if (ret < 0) + return 0; + + buf &= PCF8563_REG_CLKO_F_MASK; + return clkout_rates[ret]; +} + +static long pcf8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) + if (clkout_rates[i] <= rate) + return clkout_rates[i]; + + return 0; +} + +static int pcf8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); + struct i2c_client *client = pcf8563->client; + unsigned char buf; + int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); + int i; + + if (ret < 0) + return ret; + + for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) + if (clkout_rates[i] == rate) { + buf &= ~PCF8563_REG_CLKO_F_MASK; + buf |= i; + ret = pcf8563_write_block_data(client, + PCF8563_REG_CLKO, 1, + &buf); + return ret; + } + + return -EINVAL; +} + +static int pcf8563_clkout_control(struct clk_hw *hw, bool enable) +{ + struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); + struct i2c_client *client = pcf8563->client; + unsigned char buf; + int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); + + if (ret < 0) + return ret; + + if (enable) + buf |= PCF8563_REG_CLKO_FE; + else + buf &= ~PCF8563_REG_CLKO_FE; + + ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf); + return ret; +} + +static int pcf8563_clkout_prepare(struct clk_hw *hw) +{ + return pcf8563_clkout_control(hw, 1); +} + +static void pcf8563_clkout_unprepare(struct clk_hw *hw) +{ + pcf8563_clkout_control(hw, 0); +} + +static int pcf8563_clkout_is_prepared(struct clk_hw *hw) +{ + struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw); + struct i2c_client *client = pcf8563->client; + unsigned char buf; + int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf); + + if (ret < 0) + return ret; + + return !!(buf & PCF8563_REG_CLKO_FE); +} + +static const struct clk_ops pcf8563_clkout_ops = { + .prepare = pcf8563_clkout_prepare, + .unprepare = pcf8563_clkout_unprepare, + .is_prepared = pcf8563_clkout_is_prepared, + .recalc_rate = pcf8563_clkout_recalc_rate, + .round_rate = pcf8563_clkout_round_rate, + .set_rate = pcf8563_clkout_set_rate, +}; + +static struct clk *pcf8563_clkout_register_clk(struct pcf8563 *pcf8563) +{ + struct i2c_client *client = pcf8563->client; + struct device_node *node = client->dev.of_node; + struct clk *clk; + struct clk_init_data init; + int ret; + unsigned char buf; + + /* disable the clkout output */ + buf = 0; + ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf); + if (ret < 0) + return ERR_PTR(ret); + + init.name = "pcf8563-clkout"; + init.ops = &pcf8563_clkout_ops; + init.flags = CLK_IS_ROOT; + init.parent_names = NULL; + init.num_parents = 0; + pcf8563->clkout_hw.init = &init; + + /* optional override of the clockname */ + of_property_read_string(node, "clock-output-names", &init.name); + + /* register the clock */ + clk = clk_register(&client->dev, &pcf8563->clkout_hw); + + if (!IS_ERR(clk)) + of_clk_add_provider(node, of_clk_src_simple_get, clk); + + return clk; +} + static const struct rtc_class_ops pcf8563_rtc_ops = { .ioctl = pcf8563_rtc_ioctl, .read_time = pcf8563_rtc_read_time, @@ -459,6 +618,9 @@ static int pcf8563_probe(struct i2c_client *client, } + /* register clk in common clk framework */ + pcf8563_clkout_register_clk(pcf8563); + /* the pcf8563 alarm only supports a minute accuracy */ pcf8563->rtc->uie_unsupported = 1;