On Wed, Apr 30, 2025 at 10:03:13AM +0100, André Draszik wrote: > The Maxim MAX77759 is a companion PMIC for USB Type-C applications and > includes Battery Charger, Fuel Gauge, temperature sensors, USB Type-C > Port Controller (TCPC), NVMEM, and a GPIO expander. > > This driver exposes the non volatile memory using the platform device > registered by the core MFD driver. > > Signed-off-by: André Draszik <[email protected]>
If the plan is to take this series via mfd here is my Ack Acked-by: Srinivas Kandagatla <[email protected]> thanks, Srini > --- > v9: > * drop superfluous max77759_nvmem_is_valid() (Srini) > > v8: > * replace MODULE_ALIAS() with .id_table (Krzysztof) > * drop previous tags > > v5: > * follow API updates of max77759 core driver > > v2: > * align sentinel in max77759_nvmem_of_id[] with other max77759 drivers > (Christophe) > --- > MAINTAINERS | 1 + > drivers/nvmem/Kconfig | 12 ++++ > drivers/nvmem/Makefile | 2 + > drivers/nvmem/max77759-nvmem.c | 145 > +++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 160 insertions(+) > > diff --git a/MAINTAINERS b/MAINTAINERS > index > 0db5e1fe64930e85265913e6a7dd2669c645cf42..b821502afc48f95d48fb8c6ac6941d1dd8e63582 > 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -14670,6 +14670,7 @@ S: Maintained > F: Documentation/devicetree/bindings/*/maxim,max77759*.yaml > F: drivers/gpio/gpio-max77759.c > F: drivers/mfd/max77759.c > +F: drivers/nvmem/max77759-nvmem.c > F: include/linux/mfd/max77759.h > > MAXIM MAX77802 PMIC REGULATOR DEVICE DRIVER > diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig > index > 8671b7c974b933e147154bb40b5d41b5730518d2..3de07ef524906ad24a89e58abdfe93529a83c80f > 100644 > --- a/drivers/nvmem/Kconfig > +++ b/drivers/nvmem/Kconfig > @@ -154,6 +154,18 @@ config NVMEM_LPC18XX_OTP > To compile this driver as a module, choose M here: the module > will be called nvmem_lpc18xx_otp. > > +config NVMEM_MAX77759 > + tristate "Maxim Integrated MAX77759 NVMEM Support" > + depends on MFD_MAX77759 > + default MFD_MAX77759 > + help > + Say Y here to include support for the user-accessible storage found > + in Maxim Integrated MAX77759 PMICs. This IC provides space for 30 > + bytes of storage. > + > + This driver can also be built as a module. If so, the module > + will be called nvmem-max77759. > + > config NVMEM_MESON_EFUSE > tristate "Amlogic Meson GX eFuse Support" > depends on (ARCH_MESON || COMPILE_TEST) && MESON_SM > diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile > index > 5b77bbb6488bf89bfb305750a1cbf4a6731a0a58..a9d03cfbbd27e68d40f8c330e72e20378b12a481 > 100644 > --- a/drivers/nvmem/Makefile > +++ b/drivers/nvmem/Makefile > @@ -34,6 +34,8 @@ obj-$(CONFIG_NVMEM_LPC18XX_EEPROM) += > nvmem_lpc18xx_eeprom.o > nvmem_lpc18xx_eeprom-y := lpc18xx_eeprom.o > obj-$(CONFIG_NVMEM_LPC18XX_OTP) += nvmem_lpc18xx_otp.o > nvmem_lpc18xx_otp-y := lpc18xx_otp.o > +obj-$(CONFIG_NVMEM_MAX77759) += nvmem-max77759.o > +nvmem-max77759-y := max77759-nvmem.o > obj-$(CONFIG_NVMEM_MESON_EFUSE) += nvmem_meson_efuse.o > nvmem_meson_efuse-y := meson-efuse.o > obj-$(CONFIG_NVMEM_MESON_MX_EFUSE) += nvmem_meson_mx_efuse.o > diff --git a/drivers/nvmem/max77759-nvmem.c b/drivers/nvmem/max77759-nvmem.c > new file mode 100644 > index > 0000000000000000000000000000000000000000..c9961ad0e232e152e924b5b06d7d93172760ac3a > --- /dev/null > +++ b/drivers/nvmem/max77759-nvmem.c > @@ -0,0 +1,145 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +// > +// Copyright 2020 Google Inc > +// Copyright 2025 Linaro Ltd. > +// > +// NVMEM driver for Maxim MAX77759 > + > +#include <linux/dev_printk.h> > +#include <linux/device.h> > +#include <linux/device/driver.h> > +#include <linux/err.h> > +#include <linux/mfd/max77759.h> > +#include <linux/mod_devicetable.h> > +#include <linux/module.h> > +#include <linux/nvmem-provider.h> > +#include <linux/overflow.h> > +#include <linux/platform_device.h> > +#include <linux/string.h> > + > +#define MAX77759_NVMEM_OPCODE_HEADER_LEN 3 > +/* > + * NVMEM commands have a three byte header (which becomes part of the > command), > + * so we need to subtract that. > + */ > +#define MAX77759_NVMEM_SIZE (MAX77759_MAXQ_OPCODE_MAXLENGTH \ > + - MAX77759_NVMEM_OPCODE_HEADER_LEN) > + > +struct max77759_nvmem { > + struct device *dev; > + struct max77759 *max77759; > +}; > + > +static int max77759_nvmem_reg_read(void *priv, unsigned int offset, > + void *val, size_t bytes) > +{ > + struct max77759_nvmem *nvmem = priv; > + DEFINE_FLEX(struct max77759_maxq_command, cmd, cmd, length, > + MAX77759_NVMEM_OPCODE_HEADER_LEN); > + DEFINE_FLEX(struct max77759_maxq_response, rsp, rsp, length, > + MAX77759_MAXQ_OPCODE_MAXLENGTH); > + int ret; > + > + cmd->cmd[0] = MAX77759_MAXQ_OPCODE_USER_SPACE_READ; > + cmd->cmd[1] = offset; > + cmd->cmd[2] = bytes; > + rsp->length = bytes + MAX77759_NVMEM_OPCODE_HEADER_LEN; > + > + ret = max77759_maxq_command(nvmem->max77759, cmd, rsp); > + if (ret < 0) > + return ret; > + > + if (memcmp(cmd->cmd, rsp->rsp, MAX77759_NVMEM_OPCODE_HEADER_LEN)) { > + dev_warn(nvmem->dev, "protocol error (read)\n"); > + return -EIO; > + } > + > + memcpy(val, &rsp->rsp[MAX77759_NVMEM_OPCODE_HEADER_LEN], bytes); > + > + return 0; > +} > + > +static int max77759_nvmem_reg_write(void *priv, unsigned int offset, > + void *val, size_t bytes) > +{ > + struct max77759_nvmem *nvmem = priv; > + DEFINE_FLEX(struct max77759_maxq_command, cmd, cmd, length, > + MAX77759_MAXQ_OPCODE_MAXLENGTH); > + DEFINE_FLEX(struct max77759_maxq_response, rsp, rsp, length, > + MAX77759_MAXQ_OPCODE_MAXLENGTH); > + int ret; > + > + cmd->cmd[0] = MAX77759_MAXQ_OPCODE_USER_SPACE_WRITE; > + cmd->cmd[1] = offset; > + cmd->cmd[2] = bytes; > + memcpy(&cmd->cmd[MAX77759_NVMEM_OPCODE_HEADER_LEN], val, bytes); > + cmd->length = bytes + MAX77759_NVMEM_OPCODE_HEADER_LEN; > + rsp->length = cmd->length; > + > + ret = max77759_maxq_command(nvmem->max77759, cmd, rsp); > + if (ret < 0) > + return ret; > + > + if (memcmp(cmd->cmd, rsp->rsp, cmd->length)) { > + dev_warn(nvmem->dev, "protocol error (write)\n"); > + return -EIO; > + } > + > + return 0; > +} > + > +static int max77759_nvmem_probe(struct platform_device *pdev) > +{ > + struct nvmem_config config = { > + .dev = &pdev->dev, > + .name = dev_name(&pdev->dev), > + .id = NVMEM_DEVID_NONE, > + .type = NVMEM_TYPE_EEPROM, > + .ignore_wp = true, > + .size = MAX77759_NVMEM_SIZE, > + .word_size = sizeof(u8), > + .stride = sizeof(u8), > + .reg_read = max77759_nvmem_reg_read, > + .reg_write = max77759_nvmem_reg_write, > + }; > + struct max77759_nvmem *nvmem; > + > + nvmem = devm_kzalloc(&pdev->dev, sizeof(*nvmem), GFP_KERNEL); > + if (!nvmem) > + return -ENOMEM; > + > + nvmem->dev = &pdev->dev; > + nvmem->max77759 = dev_get_drvdata(pdev->dev.parent); > + > + config.priv = nvmem; > + > + return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config)); > +} > + > +static const struct of_device_id max77759_nvmem_of_id[] = { > + { .compatible = "maxim,max77759-nvmem", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, max77759_nvmem_of_id); > + > +static const struct platform_device_id max77759_nvmem_platform_id[] = { > + { "max77759-nvmem", }, > + { } > +}; > +MODULE_DEVICE_TABLE(platform, max77759_nvmem_platform_id); > + > +static struct platform_driver max77759_nvmem_driver = { > + .driver = { > + .name = "max77759-nvmem", > + .probe_type = PROBE_PREFER_ASYNCHRONOUS, > + .of_match_table = max77759_nvmem_of_id, > + }, > + .probe = max77759_nvmem_probe, > + .id_table = max77759_nvmem_platform_id, > +}; > + > +module_platform_driver(max77759_nvmem_driver); > + > +MODULE_AUTHOR("André Draszik <[email protected]>"); > +MODULE_DESCRIPTION("NVMEM driver for Maxim MAX77759"); > +MODULE_LICENSE("GPL"); > > -- > 2.49.0.901.g37484f566f-goog >
