A regmap field is an abstraction available in Linux. It provides to access bitfields in a regmap without having to worry about shifts and masks.

Signed-off-by: Jean-Jacques Hiblot jjhiblot@ti.com ---

drivers/core/regmap.c | 77 ++++++++++++++++++++++++++++++ include/regmap.h | 108 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 185 insertions(+)

diff --git a/drivers/core/regmap.c b/drivers/core/regmap.c index 486eea7bd4..96ac1db9b0 100644 --- a/drivers/core/regmap.c +++ b/drivers/core/regmap.c @@ -15,6 +15,14 @@ #include <dm/of_addr.h> #include <linux/ioport.h>

+struct regmap_field { + struct regmap *regmap; + unsigned int mask; + /* lsb */ + unsigned int shift; + unsigned int reg; +}; + DECLARE_GLOBAL_DATA_PTR;

/** @@ -502,3 +510,72 @@ int regmap_update_bits(struct regmap *map, uint offset, uint mask, uint val)

return regmap_write(map, offset, reg | (val & mask)); } + +int regmap_field_read(struct regmap_field *field, unsigned int *val) +{ + int ret; + unsigned int reg_val; + + ret = regmap_read(field->regmap, field->reg, &reg_val); + if (ret != 0) + return ret; + + reg_val &= field->mask; + reg_val >>= field->shift; + *val = reg_val; + + return ret; +} + +int regmap_field_write(struct regmap_field *field, unsigned int val) +{ + return regmap_update_bits(field->regmap, field->reg, field->mask, + val << field->shift); +} + +static void regmap_field_init(struct regmap_field *rm_field, + struct regmap *regmap, + struct reg_field reg_field) +{ + rm_field->regmap = regmap; + rm_field->reg = reg_field.reg; + rm_field->shift = reg_field.lsb; + rm_field->mask = GENMASK(reg_field.msb, reg_field.lsb); +} + +struct regmap_field *devm_regmap_field_alloc(struct udevice *dev, + struct regmap *regmap, + struct reg_field reg_field) +{ + struct regmap_field *rm_field = devm_kzalloc(dev, sizeof(*rm_field), + GFP_KERNEL); + if (!rm_field) + return ERR_PTR(-ENOMEM); + + regmap_field_init(rm_field, regmap, reg_field); + + return rm_field; +} + +void devm_regmap_field_free(struct udevice *dev, struct regmap_field *field) +{ + devm_kfree(dev, field); +} + +struct regmap_field *regmap_field_alloc(struct regmap *regmap, + struct reg_field reg_field) +{ + struct regmap_field *rm_field = kzalloc(sizeof(*rm_field), GFP_KERNEL); + + if (!rm_field) + return ERR_PTR(-ENOMEM); + + regmap_field_init(rm_field, regmap, reg_field); + + return rm_field; +} + +void regmap_field_free(struct regmap_field *field) +{ + kfree(field); +} diff --git a/include/regmap.h b/include/regmap.h index cc0adf568b..c1a9c8f548 100644 --- a/include/regmap.h +++ b/include/regmap.h @@ -312,6 +312,43 @@ int regmap_raw_read_range(struct regmap *map, uint range_num, uint offset, regmap_read_poll_timeout_test(map, addr, val, cond, sleep_us, \ timeout_ms, 0) \

+/** + * regmap_field_read_poll_timeout - Poll until a condition is met or a timeout + * occurs + * + * @field: Regmap field to read from + * @val: Unsigned integer variable to read the value into + * @cond: Break condition (usually involving @val) + * @sleep_us: Maximum time to sleep between reads in us (0 tight-loops). + * @timeout_ms: Timeout in ms, 0 means never timeout + * + * Returns 0 on success and -ETIMEDOUT upon a timeout or the regmap_field_read + * error return value in case of a error read. In the two former cases, + * the last read value at @addr is stored in @val. + * + * This is modelled after the regmap_read_poll_timeout macros in linux but + * with millisecond timeout. + */ +#define regmap_field_read_poll_timeout(field, val, cond, sleep_us, timeout_ms) \ +({ \ + unsigned long __start = get_timer(0); \ + int __ret; \ + for (;;) { \ + __ret = regmap_field_read((field), &(val)); \ + if (__ret) \ + break; \ + if (cond) \ + break; \ + if ((timeout_ms) && get_timer(__start) > (timeout_ms)) { \ + __ret = regmap_field_read((field), &(val)); \ + break; \ + } \ + if ((sleep_us)) \ + udelay((sleep_us)); \ + } \ + __ret ?: ((cond) ? 0 : -ETIMEDOUT); \ +}) + /** * regmap_update_bits() - Perform a read/modify/write using a mask * @@ -388,4 +425,75 @@ void *regmap_get_range(struct regmap *map, unsigned int range_num); */ int regmap_uninit(struct regmap *map);

+/** + * struct reg_field - Description of an register field + * + * @reg: Offset of the register within the regmap bank + * @lsb: lsb of the register field. + * @msb: msb of the register field. + * @id_size: port size if it has some ports + * @id_offset: address offset for each ports + */ +struct reg_field { + unsigned int reg; + unsigned int lsb; + unsigned int msb; +}; + +struct regmap_field; + +#define REG_FIELD(_reg, _lsb, _msb) { \ + .reg = _reg, \ + .lsb = _lsb, \ + .msb = _msb, \ + } + +/** + * devm_regmap_field_alloc() - Allocate and initialise a register field. + * + * @dev: Device that will be interacted with + * @regmap: regmap bank in which this register field is located. + * @reg_field: Register field with in the bank. + * + * The return value will be an ERR_PTR() on error or a valid pointer + * to a struct regmap_field. The regmap_field will be automatically freed + * by the device management code. + */ +struct regmap_field *devm_regmap_field_alloc(struct udevice *dev, + struct regmap *regmap, + struct reg_field reg_field); +/** + * devm_regmap_field_free() - Free a register field allocated using + * devm_regmap_field_alloc. + * + * @dev: Device that will be interacted with + * @field: regmap field which should be freed. + * + * Free register field allocated using devm_regmap_field_alloc(). Usually + * drivers need not call this function, as the memory allocated via devm + * will be freed as per device-driver life-cyle. + */ +void devm_regmap_field_free(struct udevice *dev, struct regmap_field *field); + +/** + * regmap_field_write() - Write a value to a regmap field + * + * @field: Regmap field to write to + * @val: Data to write to the regmap at the specified offset + * + * Return: 0 if OK, -ve on error + */ +int regmap_field_write(struct regmap_field *field, unsigned int val); + +/** + * regmap_read() - Read a 32-bit value from a regmap + * + * @field: Regmap field to write to + * @valp: Pointer to the buffer to receive the data read from the regmap + * field + * + * Return: 0 if OK, -ve on error + */ +int regmap_field_read(struct regmap_field *field, unsigned int *val); + #endif

The tests rely on a dummy driver to allocate and initialize the regmap and the regmap fields using the managed API. The first test checks that the read/write callbacks are used. The second test checks if regmap fields behave properly (mask and shift are ok) by peeking into the regmap.

Signed-off-by: Jean-Jacques Hiblot jjhiblot@ti.com

---

arch/sandbox/dts/test.dts | 13 +++ test/dm/regmap.c | 189 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 202 insertions(+)

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts index 27b0baab27..044895586a 100644 --- a/arch/sandbox/dts/test.dts +++ b/arch/sandbox/dts/test.dts @@ -862,6 +862,19 @@ mdio: mdio-test { compatible = "sandbox,mdio"; }; + + some_regmapped-bus { + #address-cells = <0x1>; + #size-cells = <0x1>; + + ranges = <0x0 0x0 0x10>; + compatible = "simple-bus"; + + regmap-test_0 { + reg = <0 0x10>; + compatible = "sandbox,regmap_test"; + }; + }; };

#include "sandbox_pmic.dtsi" diff --git a/test/dm/regmap.c b/test/dm/regmap.c index 82de295cb8..29159ccf41 100644 --- a/test/dm/regmap.c +++ b/test/dm/regmap.c @@ -171,3 +171,192 @@ static int dm_test_regmap_poll(struct unit_test_state *uts) }

DM_TEST(dm_test_regmap_poll, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); + +struct regmaptest_priv { + struct regmap *regmap; + struct regmap_field **fields; +}; + +#define REGMAP_TEST_BUF_SZ 12 +struct regmaptest_context { + unsigned short buffer[REGMAP_TEST_BUF_SZ]; +} ctx; + +static int regmaptest_write(void *context, unsigned int reg, unsigned int val) +{ + struct regmaptest_context *ctx = context; + + if (reg < ARRAY_SIZE(ctx->buffer)) { + ctx->buffer[reg] = val; + return 0; + } + return -ERANGE; +} + +static int regmaptest_read(void *context, unsigned int reg, unsigned int *val) +{ + struct regmaptest_context *ctx = context; + + if (reg < ARRAY_SIZE(ctx->buffer)) { + *val = ctx->buffer[reg]; + return 0; + } + + return -ERANGE; +} + +static struct regmap_config cfg = { + .reg_write = regmaptest_write, + .reg_read = regmaptest_read, +}; + +static const struct reg_field field_cfgs[] = { + { + .reg = 0, + .lsb = 0, + .msb = 6, + }, + { + .reg = 1, + .lsb = 4, + .msb = 12, + }, + { + .reg = 1, + .lsb = 12, + .msb = 15, + } +}; + +static int remaptest_probe(struct udevice *dev) +{ + struct regmaptest_priv *priv = dev_get_priv(dev); + struct regmap *regmap; + struct regmap_field *field; + int i; + static const int n = ARRAY_SIZE(field_cfgs); + + regmap = devm_regmap_init(dev, NULL, &ctx, &cfg); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + priv->regmap = regmap; + + priv->fields = devm_kzalloc(dev, sizeof(struct regmap_field *) * n, + GFP_KERNEL); + if (!priv->fields) + return -ENOMEM; + + for (i = 0 ; i < n; i++) { + field = devm_regmap_field_alloc(dev, regmap, field_cfgs[i]); + if (IS_ERR(field)) + return PTR_ERR(field); + priv->fields[i] = field; + } + return 0; +} + +static const struct udevice_id regmaptest_ids[] = { + { .compatible = "sandbox,regmap_test" }, + { } +}; + +U_BOOT_DRIVER(regmap_test) = { + .name = "regmaptest_drv", + .of_match = regmaptest_ids, + .id = UCLASS_NOP, + .probe = remaptest_probe, + .priv_auto_alloc_size = sizeof(struct regmaptest_priv), +}; + +static int dm_test_devm_regmap(struct unit_test_state *uts) +{ + int i = 0; + u32 val; + u16 pattern[REGMAP_TEST_BUF_SZ]; + struct udevice *dev; + struct regmaptest_priv *priv; + + ut_assertok(uclass_get_device_by_name(UCLASS_NOP, "regmap-test_0", + &dev)); + + priv = dev_get_priv(dev); + + srand(get_ticks() + rand()); + for (i = REGMAP_TEST_BUF_SZ - 1; i >= 0; i--) { + pattern[i] = rand() & 0xFFFF; + ut_assertok(regmap_write(priv->regmap, i, pattern[i])); + } + for (i = 0; i < REGMAP_TEST_BUF_SZ; i++) { + ut_assertok(regmap_read(priv->regmap, i, &val)); + ut_asserteq(val, ctx.buffer[i]); + ut_asserteq(val, pattern[i]); + } + + ut_asserteq(-ERANGE, regmap_write(priv->regmap, REGMAP_TEST_BUF_SZ, + val)); + ut_asserteq(-ERANGE, regmap_read(priv->regmap, REGMAP_TEST_BUF_SZ, + &val)); + ut_asserteq(-ERANGE, regmap_write(priv->regmap, -1, val)); + ut_asserteq(-ERANGE, regmap_read(priv->regmap, -1, &val)); + + return 0; +} +DM_TEST(dm_test_devm_regmap, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); + +static int test_one_field(struct unit_test_state *uts, + struct regmap *regmap, + struct regmap_field *field, + struct reg_field field_cfg) +{ + int j; + unsigned int val; + int mask = (1 << (field_cfg.msb - field_cfg.lsb + 1)) - 1; + int shift = field_cfg.lsb; + + ut_assertok(regmap_write(regmap, field_cfg.reg, 0)); + ut_assertok(regmap_read(regmap, field_cfg.reg, &val)); + ut_asserteq(0, val); + + for (j = 0; j <= mask; j++) { + ut_assertok(regmap_field_write(field, j)); + ut_assertok(regmap_field_read(field, &val)); + ut_asserteq(j, val); + ut_assertok(regmap_read(regmap, field_cfg.reg, &val)); + ut_asserteq(j << shift, val); + } + + ut_assertok(regmap_field_write(field, mask + 1)); + ut_assertok(regmap_read(regmap, field_cfg.reg, &val)); + ut_asserteq(0, val); + + ut_assertok(regmap_field_write(field, 0xFFFF)); + ut_assertok(regmap_read(regmap, field_cfg.reg, &val)); + ut_asserteq(mask << shift, val); + + ut_assertok(regmap_write(regmap, field_cfg.reg, 0xFFFF)); + ut_assertok(regmap_field_write(field, 0)); + ut_assertok(regmap_read(regmap, field_cfg.reg, &val)); + ut_asserteq(0xFFFF & ~(mask << shift), val); + return 0; +} + +static int dm_test_devm_regmap_field(struct unit_test_state *uts) +{ + int i, rc; + struct udevice *dev; + struct regmaptest_priv *priv; + + ut_assertok(uclass_get_device_by_name(UCLASS_NOP, "regmap-test_0", + &dev)); + priv = dev_get_priv(dev); + + for (i = 0 ; i < ARRAY_SIZE(field_cfgs); i++) { + rc = test_one_field(uts, priv->regmap, priv->fields[i], + field_cfgs[i]); + if (rc) + break; + } + + return 0; +} +DM_TEST(dm_test_devm_regmap_field, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);