[PATCH V2 1/3] watchdog: stm32: add pclk feature for stm32mp1

[ludovic.barre@st.com (Ludovic BARRE)]

On 06/20/2018 11:19 AM, Guenter Roeck wrote:
> On 06/20/2018 12:53 AM, Ludovic Barre wrote:
>> From: Ludovic Barre <ludovic.barre@st.com>
>>
>> This patch adds config data to manage specific properties by
>> compatible. Adds stm32mp1 config which requires pclk clock.
>>
>> Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
>> ---
>> ? .../devicetree/bindings/watchdog/st,stm32-iwdg.txt |? 21 +++-
>> ? drivers/watchdog/stm32_iwdg.c????????????????????? | 132 
>> ++++++++++++++-------
>> ? 2 files changed, 104 insertions(+), 49 deletions(-)
>>
>> diff --git 
>> a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt 
>> b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> index cc13b10a..f07f6d89 100644
>> --- a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> +++ b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
>> @@ -2,18 +2,31 @@ STM32 Independent WatchDoG (IWDG)
>> ? ---------------------------------
>> ? Required properties:
>> -- compatible: "st,stm32-iwdg"
>> -- reg: physical base address and length of the registers set for the 
>> device
>> -- clocks: must contain a single entry describing the clock input
>> +- compatible: Should be either "st,stm32-iwdg" or "st,stm32mp1-iwdg"
>> +- reg: Physical base address and length of the registers set for the 
>> device
>> +- clocks: Reference to the clock entry lsi. Additional pclk clock entry
>> +? is required only for st,stm32mp1-iwdg.
>> +- clock-names: Name of the clocks used.
>> +? "lsi" for st,stm32-iwdg
>> +? "pclk", "lsi" for st,stm32mp1-iwdg
>> ? Optional Properties:
>> ? - timeout-sec: Watchdog timeout value in seconds.
>> -Example:
>> +Examples:
>> ? iwdg: watchdog at 40003000 {
>> ????? compatible = "st,stm32-iwdg";
>> ????? reg = <0x40003000 0x400>;
>> ????? clocks = <&clk_lsi>;
>> +??? clock-names = "lsi";
>> +??? timeout-sec = <32>;
>> +};
>> +
>> +iwdg: iwdg at 5a002000 {
>> +??? compatible = "st,stm32mp1-iwdg";
>> +??? reg = <0x5a002000 0x400>;
>> +??? clocks = <&rcc IWDG2>, <&clk_lsi>;
>> +??? clock-names = "pclk", "lsi";
>> ????? timeout-sec = <32>;
>> ? };
>> diff --git a/drivers/watchdog/stm32_iwdg.c 
>> b/drivers/watchdog/stm32_iwdg.c
>> index c97ad56..fc96670 100644
>> --- a/drivers/watchdog/stm32_iwdg.c
>> +++ b/drivers/watchdog/stm32_iwdg.c
>> @@ -11,12 +11,13 @@
>> ? #include <linux/clk.h>
>> ? #include <linux/delay.h>
>> -#include <linux/kernel.h>
>> -#include <linux/module.h>
>> ? #include <linux/interrupt.h>
>> ? #include <linux/io.h>
>> ? #include <linux/iopoll.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> ? #include <linux/of.h>
>> +#include <linux/of_device.h>
>> ? #include <linux/platform_device.h>
>> ? #include <linux/watchdog.h>
>> @@ -54,11 +55,17 @@
>> ? #define TIMEOUT_US??? 100000
>> ? #define SLEEP_US??? 1000
>> +struct stm32_iwdg_config {
>> +??? bool has_pclk;
>> +};
>> +
> 
> This data structure is unnecessary. Just assign the boolean directly to 
> .data
> and ...
> 

Ok, I send a v3, with boolean directly to .data
like:

#define NO_PCLK		false
#define HAS_PCLK	true
...
static const struct of_device_id stm32_iwdg_of_match[] = {
	{ .compatible = "st,stm32-iwdg", .data = (void *) NO_PCLK },
	{ .compatible = "st,stm32mp1-iwdg", .data = (void *) HAS_PCLK },
	{ /* end node */ }
};

Note:
V3, because I sent my original version with V2
(it's mistake)

>> ? struct stm32_iwdg {
>> -??? struct watchdog_device??? wdd;
>> -??? void __iomem??????? *regs;
>> -??? struct clk??????? *clk;
>> -??? unsigned int??????? rate;
>> +??? struct watchdog_device??????? wdd;
>> +??? void __iomem??????????? *regs;
>> +??? struct stm32_iwdg_config??? *config;
> 
> declare bool has_pclk here.
> 
>> +??? struct clk??????????? *clk_lsi;
>> +??? struct clk??????????? *clk_pclk;
>> +??? unsigned int??????????? rate;
>> ? };
>> ? static inline u32 reg_read(void __iomem *base, u32 reg)
>> @@ -133,6 +140,44 @@ static int stm32_iwdg_set_timeout(struct 
>> watchdog_device *wdd,
>> ????? return 0;
>> ? }
>> +static int stm32_iwdg_clk_init(struct platform_device *pdev,
>> +?????????????????? struct stm32_iwdg *wdt)
>> +{
>> +??? u32 ret;
>> +
>> +??? wdt->clk_lsi = devm_clk_get(&pdev->dev, "lsi");
>> +??? if (IS_ERR(wdt->clk_lsi)) {
>> +??????? dev_err(&pdev->dev, "Unable to get lsi clock\n");
>> +??????? return PTR_ERR(wdt->clk_lsi);
>> +??? }
>> +
>> +??? /* optional peripheral clock */
>> +??? if (wdt->config->has_pclk) {
>> +??????? wdt->clk_pclk = devm_clk_get(&pdev->dev, "pclk");
>> +??????? if (IS_ERR(wdt->clk_pclk)) {
>> +??????????? dev_err(&pdev->dev, "Unable to get pclk clock\n");
>> +??????????? return PTR_ERR(wdt->clk_pclk);
>> +??????? }
>> +
>> +??????? ret = clk_prepare_enable(wdt->clk_pclk);
>> +??????? if (ret) {
>> +??????????? dev_err(&pdev->dev, "Unable to prepare pclk clock\n");
>> +??????????? return ret;
>> +??????? }
>> +??? }
>> +
>> +??? ret = clk_prepare_enable(wdt->clk_lsi);
>> +??? if (ret) {
>> +??????? dev_err(&pdev->dev, "Unable to prepare lsi clock\n");
>> +??????? clk_disable_unprepare(wdt->clk_pclk);
>> +??????? return ret;
>> +??? }
>> +
>> +??? wdt->rate = clk_get_rate(wdt->clk_lsi);
>> +
>> +??? return 0;
>> +}
>> +
>> ? static const struct watchdog_info stm32_iwdg_info = {
>> ????? .options??? = WDIOF_SETTIMEOUT |
>> ??????????????? WDIOF_MAGICCLOSE |
>> @@ -147,49 +192,50 @@ static const struct watchdog_ops stm32_iwdg_ops = {
>> ????? .set_timeout??? = stm32_iwdg_set_timeout,
>> ? };
>> +static const struct stm32_iwdg_config stm32_iwdg_cfg = {
>> +??? .has_pclk = false,
>> +};
>> +
>> +static const struct stm32_iwdg_config stm32mp1_iwdg_cfg = {
>> +??? .has_pclk = true,
>> +};
>> +
>> +static const struct of_device_id stm32_iwdg_of_match[] = {
>> +??? { .compatible = "st,stm32-iwdg", .data = &stm32_iwdg_cfg },
>> +??? { .compatible = "st,stm32mp1-iwdg", .data = &stm32mp1_iwdg_cfg },
>> +??? { /* end node */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
>> +
>> ? static int stm32_iwdg_probe(struct platform_device *pdev)
>> ? {
>> ????? struct watchdog_device *wdd;
>> +??? const struct of_device_id *match;
>> ????? struct stm32_iwdg *wdt;
>> ????? struct resource *res;
>> -??? void __iomem *regs;
>> -??? struct clk *clk;
>> ????? int ret;
>> +??? match = of_match_device(stm32_iwdg_of_match, &pdev->dev);
>> +??? if (!match || !match->data)
>> +??????? return -ENODEV;
>> +
>> +??? wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
>> +??? if (!wdt)
>> +??????? return -ENOMEM;
>> +
>> +??? wdt->config = (struct stm32_iwdg_config *)match->data;
>> +
>> ????? /* This is the timer base. */
>> ????? res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> -??? regs = devm_ioremap_resource(&pdev->dev, res);
>> -??? if (IS_ERR(regs)) {
>> +??? wdt->regs = devm_ioremap_resource(&pdev->dev, res);
>> +??? if (IS_ERR(wdt->regs)) {
>> ????????? dev_err(&pdev->dev, "Could not get resource\n");
>> -??????? return PTR_ERR(regs);
>> +??????? return PTR_ERR(wdt->regs);
>> ????? }
>> -??? clk = devm_clk_get(&pdev->dev, NULL);
>> -??? if (IS_ERR(clk)) {
>> -??????? dev_err(&pdev->dev, "Unable to get clock\n");
>> -??????? return PTR_ERR(clk);
>> -??? }
>> -
>> -??? ret = clk_prepare_enable(clk);
>> -??? if (ret) {
>> -??????? dev_err(&pdev->dev, "Unable to prepare clock %p\n", clk);
>> +??? ret = stm32_iwdg_clk_init(pdev, wdt);
>> +??? if (ret)
>> ????????? return ret;
>> -??? }
>> -
>> -??? /*
>> -???? * Allocate our watchdog driver data, which has the
>> -???? * struct watchdog_device nested within it.
>> -???? */
>> -??? wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
>> -??? if (!wdt) {
>> -??????? ret = -ENOMEM;
>> -??????? goto err;
>> -??? }
>> -
>> -??? /* Initialize struct stm32_iwdg. */
>> -??? wdt->regs = regs;
>> -??? wdt->clk = clk;
>> -??? wdt->rate = clk_get_rate(clk);
>> ????? /* Initialize struct watchdog_device. */
>> ????? wdd = &wdt->wdd;
>> @@ -217,7 +263,8 @@ static int stm32_iwdg_probe(struct platform_device 
>> *pdev)
>> ????? return 0;
>> ? err:
>> -??? clk_disable_unprepare(clk);
>> +??? clk_disable_unprepare(wdt->clk_lsi);
>> +??? clk_disable_unprepare(wdt->clk_pclk);
>> ????? return ret;
>> ? }
>> @@ -227,23 +274,18 @@ static int stm32_iwdg_remove(struct 
>> platform_device *pdev)
>> ????? struct stm32_iwdg *wdt = platform_get_drvdata(pdev);
>> ????? watchdog_unregister_device(&wdt->wdd);
>> -??? clk_disable_unprepare(wdt->clk);
>> +??? clk_disable_unprepare(wdt->clk_lsi);
>> +??? clk_disable_unprepare(wdt->clk_pclk);
>> ????? return 0;
>> ? }
>> -static const struct of_device_id stm32_iwdg_of_match[] = {
>> -??? { .compatible = "st,stm32-iwdg" },
>> -??? { /* end node */ }
>> -};
>> -MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
>> -
>> ? static struct platform_driver stm32_iwdg_driver = {
>> ????? .probe??????? = stm32_iwdg_probe,
>> ????? .remove??????? = stm32_iwdg_remove,
>> ????? .driver = {
>> ????????? .name??? = "iwdg",
>> -??????? .of_match_table = stm32_iwdg_of_match,
>> +??????? .of_match_table = of_match_ptr(stm32_iwdg_of_match),
>> ????? },
>> ? };
>> ? module_platform_driver(stm32_iwdg_driver);
>>
>