#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
-#include <linux/sysfs.h>
+#include <linux/nvmem-provider.h>
+#include <linux/regmap.h>
#include <linux/eeprom_93xx46.h>
#define OP_START 0x4
#define ADDR_ERAL 0x20
#define ADDR_EWEN 0x30
+struct eeprom_93xx46_devtype_data {
+ unsigned int quirks;
+};
+
+static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = {
+ .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ |
+ EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH,
+};
+
struct eeprom_93xx46_dev {
struct spi_device *spi;
struct eeprom_93xx46_platform_data *pdata;
- struct bin_attribute bin;
struct mutex lock;
+ struct regmap_config regmap_config;
+ struct nvmem_config nvmem_config;
+ struct nvmem_device *nvmem;
int addrlen;
+ int size;
};
+static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev)
+{
+ return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ;
+}
+
+static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev)
+{
+ return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH;
+}
+
static ssize_t
-eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t count)
+eeprom_93xx46_read(struct eeprom_93xx46_dev *edev, char *buf,
+ unsigned off, size_t count)
{
- struct eeprom_93xx46_dev *edev;
- struct device *dev;
- struct spi_message m;
- struct spi_transfer t[2];
- int bits, ret;
- u16 cmd_addr;
+ ssize_t ret = 0;
- dev = container_of(kobj, struct device, kobj);
- edev = dev_get_drvdata(dev);
+ if (unlikely(off >= edev->size))
+ return 0;
+ if ((off + count) > edev->size)
+ count = edev->size - off;
+ if (unlikely(!count))
+ return count;
- cmd_addr = OP_READ << edev->addrlen;
+ mutex_lock(&edev->lock);
- if (edev->addrlen == 7) {
- cmd_addr |= off & 0x7f;
- bits = 10;
- } else {
- cmd_addr |= off & 0x3f;
- bits = 9;
- }
+ if (edev->pdata->prepare)
+ edev->pdata->prepare(edev);
- dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
- cmd_addr, edev->spi->max_speed_hz);
+ while (count) {
+ struct spi_message m;
+ struct spi_transfer t[2] = { { 0 } };
+ u16 cmd_addr = OP_READ << edev->addrlen;
+ size_t nbytes = count;
+ int bits;
+ int err;
+
+ if (edev->addrlen == 7) {
+ cmd_addr |= off & 0x7f;
+ bits = 10;
+ if (has_quirk_single_word_read(edev))
+ nbytes = 1;
+ } else {
+ cmd_addr |= (off >> 1) & 0x3f;
+ bits = 9;
+ if (has_quirk_single_word_read(edev))
+ nbytes = 2;
+ }
- spi_message_init(&m);
- memset(t, 0, sizeof(t));
+ dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
+ cmd_addr, edev->spi->max_speed_hz);
- t[0].tx_buf = (char *)&cmd_addr;
- t[0].len = 2;
- t[0].bits_per_word = bits;
- spi_message_add_tail(&t[0], &m);
+ spi_message_init(&m);
- t[1].rx_buf = buf;
- t[1].len = count;
- t[1].bits_per_word = 8;
- spi_message_add_tail(&t[1], &m);
+ t[0].tx_buf = (char *)&cmd_addr;
+ t[0].len = 2;
+ t[0].bits_per_word = bits;
+ spi_message_add_tail(&t[0], &m);
- mutex_lock(&edev->lock);
+ t[1].rx_buf = buf;
+ t[1].len = count;
+ t[1].bits_per_word = 8;
+ spi_message_add_tail(&t[1], &m);
- if (edev->pdata->prepare)
- edev->pdata->prepare(edev);
+ err = spi_sync(edev->spi, &m);
+ /* have to wait at least Tcsl ns */
+ ndelay(250);
- ret = spi_sync(edev->spi, &m);
- /* have to wait at least Tcsl ns */
- ndelay(250);
- if (ret) {
- dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
- count, (int)off, ret);
+ if (err) {
+ dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
+ nbytes, (int)off, err);
+ ret = err;
+ break;
+ }
+
+ buf += nbytes;
+ off += nbytes;
+ count -= nbytes;
+ ret += nbytes;
}
if (edev->pdata->finish)
edev->pdata->finish(edev);
mutex_unlock(&edev->lock);
- return ret ? : count;
+ return ret;
}
static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
bits = 9;
}
- dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr);
+ if (has_quirk_instruction_length(edev)) {
+ cmd_addr <<= 2;
+ bits += 2;
+ }
+
+ dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n",
+ is_on ? "en" : "ds", cmd_addr, bits);
spi_message_init(&m);
memset(&t, 0, sizeof(t));
bits = 10;
data_len = 1;
} else {
- cmd_addr |= off & 0x3f;
+ cmd_addr |= (off >> 1) & 0x3f;
bits = 9;
data_len = 2;
}
}
static ssize_t
-eeprom_93xx46_bin_write(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t count)
+eeprom_93xx46_write(struct eeprom_93xx46_dev *edev, const char *buf,
+ loff_t off, size_t count)
{
- struct eeprom_93xx46_dev *edev;
- struct device *dev;
int i, ret, step = 1;
- dev = container_of(kobj, struct device, kobj);
- edev = dev_get_drvdata(dev);
+ if (unlikely(off >= edev->size))
+ return -EFBIG;
+ if ((off + count) > edev->size)
+ count = edev->size - off;
+ if (unlikely(!count))
+ return count;
/* only write even number of bytes on 16-bit devices */
if (edev->addrlen == 6) {
return ret ? : count;
}
+/*
+ * Provide a regmap interface, which is registered with the NVMEM
+ * framework
+*/
+static int eeprom_93xx46_regmap_read(void *context, const void *reg,
+ size_t reg_size, void *val,
+ size_t val_size)
+{
+ struct eeprom_93xx46_dev *eeprom_93xx46 = context;
+ off_t offset = *(u32 *)reg;
+ int err;
+
+ err = eeprom_93xx46_read(eeprom_93xx46, val, offset, val_size);
+ if (err)
+ return err;
+ return 0;
+}
+
+static int eeprom_93xx46_regmap_write(void *context, const void *data,
+ size_t count)
+{
+ struct eeprom_93xx46_dev *eeprom_93xx46 = context;
+ const char *buf;
+ u32 offset;
+ size_t len;
+ int err;
+
+ memcpy(&offset, data, sizeof(offset));
+ buf = (const char *)data + sizeof(offset);
+ len = count - sizeof(offset);
+
+ err = eeprom_93xx46_write(eeprom_93xx46, buf, offset, len);
+ if (err)
+ return err;
+ return 0;
+}
+
+static const struct regmap_bus eeprom_93xx46_regmap_bus = {
+ .read = eeprom_93xx46_regmap_read,
+ .write = eeprom_93xx46_regmap_write,
+ .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
{
struct eeprom_93xx46_platform_data *pd = edev->pdata;
bits = 9;
}
+ if (has_quirk_instruction_length(edev)) {
+ cmd_addr <<= 2;
+ bits += 2;
+ }
+
+ dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits);
+
spi_message_init(&m);
memset(&t, 0, sizeof(t));
}
static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
+static void select_assert(void *context)
+{
+ struct eeprom_93xx46_dev *edev = context;
+
+ gpiod_set_value_cansleep(edev->pdata->select, 1);
+}
+
+static void select_deassert(void *context)
+{
+ struct eeprom_93xx46_dev *edev = context;
+
+ gpiod_set_value_cansleep(edev->pdata->select, 0);
+}
+
+static const struct of_device_id eeprom_93xx46_of_table[] = {
+ { .compatible = "eeprom-93xx46", },
+ { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
+ {}
+};
+MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
+
+static int eeprom_93xx46_probe_dt(struct spi_device *spi)
+{
+ const struct of_device_id *of_id =
+ of_match_device(eeprom_93xx46_of_table, &spi->dev);
+ struct device_node *np = spi->dev.of_node;
+ struct eeprom_93xx46_platform_data *pd;
+ u32 tmp;
+ int gpio;
+ enum of_gpio_flags of_flags;
+ int ret;
+
+ pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;
+
+ ret = of_property_read_u32(np, "data-size", &tmp);
+ if (ret < 0) {
+ dev_err(&spi->dev, "data-size property not found\n");
+ return ret;
+ }
+
+ if (tmp == 8) {
+ pd->flags |= EE_ADDR8;
+ } else if (tmp == 16) {
+ pd->flags |= EE_ADDR16;
+ } else {
+ dev_err(&spi->dev, "invalid data-size (%d)\n", tmp);
+ return -EINVAL;
+ }
+
+ if (of_property_read_bool(np, "read-only"))
+ pd->flags |= EE_READONLY;
+
+ gpio = of_get_named_gpio_flags(np, "select-gpios", 0, &of_flags);
+ if (gpio_is_valid(gpio)) {
+ unsigned long flags =
+ of_flags == OF_GPIO_ACTIVE_LOW ? GPIOF_ACTIVE_LOW : 0;
+
+ ret = devm_gpio_request_one(&spi->dev, gpio, flags,
+ "eeprom_93xx46_select");
+ if (ret)
+ return ret;
+
+ pd->select = gpio_to_desc(gpio);
+ pd->prepare = select_assert;
+ pd->finish = select_deassert;
+
+ gpiod_direction_output(pd->select, 0);
+ }
+
+ if (of_id->data) {
+ const struct eeprom_93xx46_devtype_data *data = of_id->data;
+
+ pd->quirks = data->quirks;
+ }
+
+ spi->dev.platform_data = pd;
+
+ return 0;
+}
+
static int eeprom_93xx46_probe(struct spi_device *spi)
{
struct eeprom_93xx46_platform_data *pd;
struct eeprom_93xx46_dev *edev;
+ struct regmap *regmap;
int err;
+ if (spi->dev.of_node) {
+ err = eeprom_93xx46_probe_dt(spi);
+ if (err < 0)
+ return err;
+ }
+
pd = spi->dev.platform_data;
if (!pd) {
dev_err(&spi->dev, "missing platform data\n");
edev->spi = spi_dev_get(spi);
edev->pdata = pd;
- sysfs_bin_attr_init(&edev->bin);
- edev->bin.attr.name = "eeprom";
- edev->bin.attr.mode = S_IRUSR;
- edev->bin.read = eeprom_93xx46_bin_read;
- edev->bin.size = 128;
- if (!(pd->flags & EE_READONLY)) {
- edev->bin.write = eeprom_93xx46_bin_write;
- edev->bin.attr.mode |= S_IWUSR;
+ edev->size = 128;
+
+ edev->regmap_config.reg_bits = 32;
+ edev->regmap_config.val_bits = 8;
+ edev->regmap_config.reg_stride = 1;
+ edev->regmap_config.max_register = edev->size - 1;
+
+ regmap = devm_regmap_init(&spi->dev, &eeprom_93xx46_regmap_bus, edev,
+ &edev->regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&spi->dev, "regmap init failed\n");
+ err = PTR_ERR(regmap);
+ goto fail;
}
- err = sysfs_create_bin_file(&spi->dev.kobj, &edev->bin);
- if (err)
+ edev->nvmem_config.name = dev_name(&spi->dev);
+ edev->nvmem_config.dev = &spi->dev;
+ edev->nvmem_config.read_only = pd->flags & EE_READONLY;
+ edev->nvmem_config.root_only = true;
+ edev->nvmem_config.owner = THIS_MODULE;
+ edev->nvmem_config.compat = true;
+ edev->nvmem_config.base_dev = &spi->dev;
+
+ edev->nvmem = nvmem_register(&edev->nvmem_config);
+ if (IS_ERR(edev->nvmem)) {
+ err = PTR_ERR(edev->nvmem);
goto fail;
+ }
dev_info(&spi->dev, "%d-bit eeprom %s\n",
(pd->flags & EE_ADDR8) ? 8 : 16,
{
struct eeprom_93xx46_dev *edev = spi_get_drvdata(spi);
+ nvmem_unregister(edev->nvmem);
+
if (!(edev->pdata->flags & EE_READONLY))
device_remove_file(&spi->dev, &dev_attr_erase);
- sysfs_remove_bin_file(&spi->dev.kobj, &edev->bin);
kfree(edev);
return 0;
}
static struct spi_driver eeprom_93xx46_driver = {
.driver = {
.name = "93xx46",
+ .of_match_table = of_match_ptr(eeprom_93xx46_of_table),
},
.probe = eeprom_93xx46_probe,
.remove = eeprom_93xx46_remove,
projects / deliverable / linux.git / blobdiff