Message ID | 20200616172904.373045-1-lee.jones@linaro.org |
---|---|
State | New |
Headers | show |
Series | [1/1] mfd: Add I2C based System Configuaration (SYSCON) access | expand |
On Tue, 16 Jun 2020, Lee Jones wrote: > The existing SYSCON implementation only supports MMIO (memory mapped) > accesses, facilitated by Regmap. This extends support for registers > held behind I2C busses. > > Signed-off-by: Lee Jones <lee.jones@linaro.org> > --- > drivers/mfd/Kconfig | 7 +++ > drivers/mfd/Makefile | 1 + > drivers/mfd/syscon-i2c.c | 89 ++++++++++++++++++++++++++++++++++ > include/linux/mfd/syscon-i2c.h | 26 ++++++++++ > 4 files changed, 123 insertions(+) > create mode 100644 drivers/mfd/syscon-i2c.c > create mode 100644 include/linux/mfd/syscon-i2c.h > > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig > index 0a59249198d34..63ae78b92b086 100644 > --- a/drivers/mfd/Kconfig > +++ b/drivers/mfd/Kconfig > @@ -1300,6 +1300,13 @@ config MFD_SYSCON > Select this option to enable accessing system control registers > via regmap. > > +config MFD_SYSCON_I2C > + bool "System Controller Register R/W Based on I2C Regmap" > + select REGMAP_I2C > + help > + Select this option to enable accessing system control registers > + via I2C using regmap. > + > config MFD_DAVINCI_VOICECODEC > tristate > select MFD_CORE > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile > index f935d10cbf0fc..0aec1f42ac979 100644 > --- a/drivers/mfd/Makefile > +++ b/drivers/mfd/Makefile > @@ -219,6 +219,7 @@ obj-$(CONFIG_MFD_RK808) += rk808.o > obj-$(CONFIG_MFD_RN5T618) += rn5t618.o > obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o > obj-$(CONFIG_MFD_SYSCON) += syscon.o > +obj-$(CONFIG_MFD_SYSCON_I2C) += syscon-i2c.o > obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o > obj-$(CONFIG_MFD_VEXPRESS_SYSREG) += vexpress-sysreg.o > obj-$(CONFIG_MFD_RETU) += retu-mfd.o > diff --git a/drivers/mfd/syscon-i2c.c b/drivers/mfd/syscon-i2c.c > new file mode 100644 > index 0000000000000..404e595d7646c > --- /dev/null > +++ b/drivers/mfd/syscon-i2c.c > @@ -0,0 +1,89 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * System Control Driver accessed over I2C > + * > + * Copyright (C) 2020 Linaro Ltd. > + * > + * Author: Lee Jones <lee.jones@linaro.org> > + */ > + > +#include <linux/err.h> > +#include <linux/i2c.h> > +#include <linux/list.h> > +#include <linux/mfd/syscon-i2c.h> > +#include <linux/regmap.h> > + > +static DEFINE_SPINLOCK(syscon_i2c_list_slock); > +static LIST_HEAD(syscon_i2c_list); > + > +struct syscon { > + struct device_node *np; Note to self: struct i2c_client *client; > + struct regmap *regmap; > + struct list_head list; > +}; > + > +static const struct regmap_config syscon_i2c_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +static struct syscon *of_syscon_i2c_register(struct i2c_client *client) > +{ > + struct regmap_config syscon_config = syscon_i2c_regmap_config; > + struct device_node *np = client->dev.of_node; > + struct syscon *syscon; > + struct regmap *regmap; > + int ret; > + > + syscon = devm_kzalloc(&client->dev, sizeof(*syscon), GFP_KERNEL); > + if (!syscon) > + return ERR_PTR(-ENOMEM); > + > + syscon_config.name = of_node_full_name(np); Note to self: Use dev_name(); > + regmap = devm_regmap_init_i2c(client, &syscon_config); > + if (IS_ERR(regmap)) { > + dev_err(&client->dev, "Failed to initialise Regmap I2C\n"); > + ret = PTR_ERR(regmap); > + return ERR_PTR(ret); > + } > + > + syscon->regmap = regmap; > + syscon->np = np; > + > + spin_lock(&syscon_i2c_list_slock); > + list_add_tail(&syscon->list, &syscon_i2c_list); > + spin_unlock(&syscon_i2c_list_slock); > + > + return syscon; > +} > + > +static struct regmap *i2c_device_node_get_regmap(struct i2c_client *client) Note to self: i2c_client_get_regmap() > +{ > + struct device_node *np = client->dev.of_node; > + struct syscon *entry, *syscon = NULL; > + > + spin_lock(&syscon_i2c_list_slock); > + > + list_for_each_entry(entry, &syscon_i2c_list, list) > + if (entry->np == np) { > + syscon = entry; > + break; > + } > + > + spin_unlock(&syscon_i2c_list_slock); > + > + if (!syscon) > + syscon = of_syscon_i2c_register(client); > + > + if (IS_ERR(syscon)) > + return ERR_CAST(syscon); > + > + return syscon->regmap; > +} > + > +struct regmap *i2c_device_node_to_regmap(struct i2c_client *client) Note to self: i2c_client_to_regmap() > +{ > + return i2c_device_node_get_regmap(client); > +} > +EXPORT_SYMBOL_GPL(i2c_device_node_to_regmap); > diff --git a/include/linux/mfd/syscon-i2c.h b/include/linux/mfd/syscon-i2c.h > new file mode 100644 > index 0000000000000..854e316fec93e > --- /dev/null > +++ b/include/linux/mfd/syscon-i2c.h > @@ -0,0 +1,26 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * System Control Driver accessed via I2C > + * > + * Copyright (C) 2020 Linaro Ltd. > + * > + * Author: Lee Jones <lee.jones@linaro.org> > + */ > + > +#ifndef __LINUX_MFD_SYSCON_I2C_H__ > +#define __LINUX_MFD_SYSCON_I2C_H__ > + > +#include <linux/err.h> > +#include <linux/errno.h> > +#include <linux/i2c.h> > + > +#ifdef CONFIG_MFD_SYSCON_I2C > +extern struct regmap *i2c_device_node_to_regmap(struct i2c_client *client); > +#else > +static inline struct regmap *i2c_device_node_to_regmap(struct i2c_client *client) > +{ > + return ERR_PTR(-ENOTSUPP); > +} > +#endif > + > +#endif /* __LINUX_MFD_SYSCON_I2C_H__ */ -- Lee Jones [李琼斯] Senior Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog
Hi Lee, I love your patch! Yet something to improve: [auto build test ERROR on ljones-mfd/for-mfd-next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Lee-Jones/mfd-Add-I2C-based-System-Configuaration-SYSCON-access/20200617-013251 base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next config: h8300-allmodconfig (attached as .config) compiler: h8300-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=h8300 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@intel.com> All errors (new ones prefixed by >>, old ones prefixed by <<): h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_byte_reg_read': >> regmap-i2c.c:(.text+0x167): undefined reference to `i2c_smbus_read_byte_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_byte_reg_write': >> regmap-i2c.c:(.text+0x1a7): undefined reference to `i2c_smbus_write_byte_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_word_reg_read': >> regmap-i2c.c:(.text+0x1d3): undefined reference to `i2c_smbus_read_word_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_word_read_swapped': regmap-i2c.c:(.text+0x211): undefined reference to `i2c_smbus_read_word_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_word_write_swapped': >> regmap-i2c.c:(.text+0x25b): undefined reference to `i2c_smbus_write_word_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_smbus_word_reg_write': regmap-i2c.c:(.text+0x285): undefined reference to `i2c_smbus_write_word_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_i2c_smbus_i2c_read': >> regmap-i2c.c:(.text+0x2c3): undefined reference to `i2c_smbus_read_i2c_block_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_i2c_smbus_i2c_write': >> regmap-i2c.c:(.text+0x30d): undefined reference to `i2c_smbus_write_i2c_block_data' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_i2c_read': >> regmap-i2c.c:(.text+0x37d): undefined reference to `i2c_transfer' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_i2c_gather_write': regmap-i2c.c:(.text+0x431): undefined reference to `i2c_transfer' h8300-linux-ld: drivers/base/regmap/regmap-i2c.o: in function `regmap_i2c_write': >> regmap-i2c.c:(.text+0x485): undefined reference to `i2c_transfer_buffer_flags' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 0a59249198d34..63ae78b92b086 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -1300,6 +1300,13 @@ config MFD_SYSCON Select this option to enable accessing system control registers via regmap. +config MFD_SYSCON_I2C + bool "System Controller Register R/W Based on I2C Regmap" + select REGMAP_I2C + help + Select this option to enable accessing system control registers + via I2C using regmap. + config MFD_DAVINCI_VOICECODEC tristate select MFD_CORE diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index f935d10cbf0fc..0aec1f42ac979 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -219,6 +219,7 @@ obj-$(CONFIG_MFD_RK808) += rk808.o obj-$(CONFIG_MFD_RN5T618) += rn5t618.o obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o obj-$(CONFIG_MFD_SYSCON) += syscon.o +obj-$(CONFIG_MFD_SYSCON_I2C) += syscon-i2c.o obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o obj-$(CONFIG_MFD_VEXPRESS_SYSREG) += vexpress-sysreg.o obj-$(CONFIG_MFD_RETU) += retu-mfd.o diff --git a/drivers/mfd/syscon-i2c.c b/drivers/mfd/syscon-i2c.c new file mode 100644 index 0000000000000..404e595d7646c --- /dev/null +++ b/drivers/mfd/syscon-i2c.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * System Control Driver accessed over I2C + * + * Copyright (C) 2020 Linaro Ltd. + * + * Author: Lee Jones <lee.jones@linaro.org> + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/list.h> +#include <linux/mfd/syscon-i2c.h> +#include <linux/regmap.h> + +static DEFINE_SPINLOCK(syscon_i2c_list_slock); +static LIST_HEAD(syscon_i2c_list); + +struct syscon { + struct device_node *np; + struct regmap *regmap; + struct list_head list; +}; + +static const struct regmap_config syscon_i2c_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static struct syscon *of_syscon_i2c_register(struct i2c_client *client) +{ + struct regmap_config syscon_config = syscon_i2c_regmap_config; + struct device_node *np = client->dev.of_node; + struct syscon *syscon; + struct regmap *regmap; + int ret; + + syscon = devm_kzalloc(&client->dev, sizeof(*syscon), GFP_KERNEL); + if (!syscon) + return ERR_PTR(-ENOMEM); + + syscon_config.name = of_node_full_name(np); + + regmap = devm_regmap_init_i2c(client, &syscon_config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "Failed to initialise Regmap I2C\n"); + ret = PTR_ERR(regmap); + return ERR_PTR(ret); + } + + syscon->regmap = regmap; + syscon->np = np; + + spin_lock(&syscon_i2c_list_slock); + list_add_tail(&syscon->list, &syscon_i2c_list); + spin_unlock(&syscon_i2c_list_slock); + + return syscon; +} + +static struct regmap *i2c_device_node_get_regmap(struct i2c_client *client) +{ + struct device_node *np = client->dev.of_node; + struct syscon *entry, *syscon = NULL; + + spin_lock(&syscon_i2c_list_slock); + + list_for_each_entry(entry, &syscon_i2c_list, list) + if (entry->np == np) { + syscon = entry; + break; + } + + spin_unlock(&syscon_i2c_list_slock); + + if (!syscon) + syscon = of_syscon_i2c_register(client); + + if (IS_ERR(syscon)) + return ERR_CAST(syscon); + + return syscon->regmap; +} + +struct regmap *i2c_device_node_to_regmap(struct i2c_client *client) +{ + return i2c_device_node_get_regmap(client); +} +EXPORT_SYMBOL_GPL(i2c_device_node_to_regmap); diff --git a/include/linux/mfd/syscon-i2c.h b/include/linux/mfd/syscon-i2c.h new file mode 100644 index 0000000000000..854e316fec93e --- /dev/null +++ b/include/linux/mfd/syscon-i2c.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * System Control Driver accessed via I2C + * + * Copyright (C) 2020 Linaro Ltd. + * + * Author: Lee Jones <lee.jones@linaro.org> + */ + +#ifndef __LINUX_MFD_SYSCON_I2C_H__ +#define __LINUX_MFD_SYSCON_I2C_H__ + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> + +#ifdef CONFIG_MFD_SYSCON_I2C +extern struct regmap *i2c_device_node_to_regmap(struct i2c_client *client); +#else +static inline struct regmap *i2c_device_node_to_regmap(struct i2c_client *client) +{ + return ERR_PTR(-ENOTSUPP); +} +#endif + +#endif /* __LINUX_MFD_SYSCON_I2C_H__ */
The existing SYSCON implementation only supports MMIO (memory mapped) accesses, facilitated by Regmap. This extends support for registers held behind I2C busses. Signed-off-by: Lee Jones <lee.jones@linaro.org> --- drivers/mfd/Kconfig | 7 +++ drivers/mfd/Makefile | 1 + drivers/mfd/syscon-i2c.c | 89 ++++++++++++++++++++++++++++++++++ include/linux/mfd/syscon-i2c.h | 26 ++++++++++ 4 files changed, 123 insertions(+) create mode 100644 drivers/mfd/syscon-i2c.c create mode 100644 include/linux/mfd/syscon-i2c.h -- 2.25.1