From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pankaj Dubey Subject: RE: [PATCH v3 1/6] i2c: s3c2410: Handle i2c sys_cfg register in i2c driver Date: Tue, 17 Jun 2014 09:51:39 +0530 Message-ID: <000301cf89e3$a43d3550$ecb79ff0$@samsung.com> References: <1399706287-13919-1-git-send-email-y@samsung.com> <1399706419-13976-1-git-send-email-pankaj.dubey@samsung.com> <1399706419-13976-2-git-send-email-pankaj.dubey@samsung.com> <53970994.8010400@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <53970994.8010400@samsung.com> Content-language: en-us Sender: linux-doc-owner@vger.kernel.org To: 'Tomasz Figa' , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: kgene.kim@samsung.com, arnd@arndb.de, 'Rob Herring' , 'Randy Dunlap' , 'Wolfram Sang' , 'Russell King' , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-i2c@vger.kernel.org List-Id: devicetree@vger.kernel.org Hi Tomasz, > > Hi Pankaj, > > On 10.05.2014 09:20, Pankaj Dubey wrote: > > Let's handle i2c interrupt re-configuration in i2c driver. This will > > help us in removing some soc specific checks from machine files. > > Since only Exynos5250, and Exynos5420 need to do this, added syscon > > based phandle to i2c device nodes of respective SoC DT files. > > Also handle saving and restoring of SYS_I2C_CFG register during > > suspend and resume of i2c driver. This will help in removing soc > > specific check from mach-exynos/pm.c. > > > > CC: Rob Herring > > CC: Randy Dunlap > > CC: Wolfram Sang > > CC: Russell King > > CC: devicetree@vger.kernel.org > > CC: linux-doc@vger.kernel.org > > CC: linux-i2c@vger.kernel.org > > Signed-off-by: Pankaj Dubey > > --- > > .../devicetree/bindings/arm/samsung/sysreg.txt | 1 + > > arch/arm/boot/dts/exynos5.dtsi | 5 +++ > > arch/arm/boot/dts/exynos5250.dtsi | 4 +++ > > arch/arm/boot/dts/exynos5420.dtsi | 4 +++ > > What about Exynos5410 and Exynos5800? OK, I will check user manuals of these two SoCs and if required will update. > > > drivers/i2c/busses/i2c-s3c2410.c | 32 > ++++++++++++++++++++ > > 5 files changed, 46 insertions(+) > > [snip] > > > diff --git a/drivers/i2c/busses/i2c-s3c2410.c > > b/drivers/i2c/busses/i2c-s3c2410.c > > index ae44910..e707062 100644 > > --- a/drivers/i2c/busses/i2c-s3c2410.c > > +++ b/drivers/i2c/busses/i2c-s3c2410.c > > @@ -39,6 +39,8 @@ > > #include > > #include > > #include > > +#include > > +#include > > > > #include > > > > @@ -91,6 +93,9 @@ > > /* Max time to wait for bus to become idle after a xfer (in us) */ > > #define S3C2410_IDLE_TIMEOUT 5000 > > > > +/* Exynos5 Sysreg offset */ > > +#define EXYNOS5_SYS_I2C_CFG 0x0234 > > + > > /* i2c controller state */ > > enum s3c24xx_i2c_state { > > STATE_IDLE, > > @@ -127,6 +132,8 @@ struct s3c24xx_i2c { #if > > defined(CONFIG_ARM_S3C24XX_CPUFREQ) > > struct notifier_block freq_transition; > > #endif > > + struct regmap *sysreg; > > + unsigned int sys_i2s_cfg; > > typo: s/i2s/i2c/ Oops, sorry I will correct this. > > > }; > > > > static struct platform_device_id s3c24xx_driver_ids[] = { @@ -1075,6 > > +1082,8 @@ static void s3c24xx_i2c_parse_dt(struct device_node *np, > > struct s3c24xx_i2c *i2c) { > > struct s3c2410_platform_i2c *pdata = i2c->pdata; > > + u32 val = 0; > > + int id; > > > > if (!np) > > return; > > @@ -1084,6 +1093,23 @@ s3c24xx_i2c_parse_dt(struct device_node *np, struct > s3c24xx_i2c *i2c) > > of_property_read_u32(np, "samsung,i2c-slave-addr", &pdata->slave_addr); > > of_property_read_u32(np, "samsung,i2c-max-bus-freq", > > (u32 *)&pdata->frequency); > > + /* > > + * Exynos5's legacy i2c controller and new high speed i2c > > + * controller have muxed interrupt sources. By default the > > What do you mean by "by default"? Is it a setting from the bootloader or reset value? > It's a reset value. > Probably to ensure that the mux is set correctly, same thing should be also added to > hsi2c driver. > > > + * interrupts for 4-channel HS-I2C controller are enabled. > > + * If node for first four channels of legacy i2c controller > > + * are available then re-configure the interrupts via the > > + * system register. > > + */ > > + id = of_alias_get_id(np, "i2c"); > > + i2c->sysreg = syscon_regmap_lookup_by_phandle(np, > > + "samsung,syscon-phandle"); > > + if (IS_ERR(i2c->sysreg)) { > > + /* As this is not compulsory do not return error */ > > + pr_info("i2c-%d skipping re-configuration of interrutps\n", id); > > + return; > > + } > > + regmap_update_bits(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, BIT(id), val); > > As Wolfram pointed, val can be replaced with immediate 0 here. OK, I will take care as per suggestion. > > > } > > #else > > static void > > @@ -1268,6 +1294,9 @@ static int s3c24xx_i2c_suspend_noirq(struct > > device *dev) > > > > i2c->suspended = 1; > > > > + if (!IS_ERR(i2c->sysreg)) > > + regmap_read(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, &i2c- > >sys_i2s_cfg); > > + > > return 0; > > } > > > > @@ -1276,6 +1305,9 @@ static int s3c24xx_i2c_resume(struct device *dev) > > struct platform_device *pdev = to_platform_device(dev); > > struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); > > > > + if (!IS_ERR(i2c->sysreg)) > > + regmap_write(i2c->sysreg, i2c->sys_i2s_cfg, > EXYNOS5_SYS_I2C_CFG); > > According to include/linux/regmap.h: > > int regmap_write(struct regmap *map, unsigned int reg, unsigned int val); > > So in your code reg is swapped with val. Yes. I will correct this. > > Best regards, > Tomasz