@@ -16,6 +16,18 @@
#include <dt-bindings/soc/samsung,exynos-usi.h>
+/* USIv1: System Register: SW_CONF register bits */
+#define USI_V1_SW_CONF_NONE 0x0
+#define USI_V1_SW_CONF_I2C0 0x1
+#define USI_V1_SW_CONF_I2C1 0x2
+#define USI_V1_SW_CONF_I2C0_1 0x3
+#define USI_V1_SW_CONF_SPI 0x4
+#define USI_V1_SW_CONF_UART 0x8
+#define USI_V1_SW_CONF_UART_I2C1 0xa
+#define USI_V1_SW_CONF_MASK (USI_V1_SW_CONF_I2C0 | USI_V1_SW_CONF_I2C1 | \
+ USI_V1_SW_CONF_I2C0_1 | USI_V1_SW_CONF_SPI | \
+ USI_V1_SW_CONF_UART | USI_V1_SW_CONF_UART_I2C1)
+
/* USIv2: System Register: SW_CONF register bits */
#define USI_V2_SW_CONF_NONE 0x0
#define USI_V2_SW_CONF_UART BIT(0)
@@ -34,7 +46,8 @@
#define USI_OPTION_CLKSTOP_ON BIT(2)
enum exynos_usi_ver {
- USI_VER2 = 2,
+ USI_VER1 = 1,
+ USI_VER2,
};
struct exynos_usi_variant {
@@ -66,19 +79,39 @@ struct exynos_usi_mode {
unsigned int val; /* mode register value */
};
-static const struct exynos_usi_mode exynos_usi_modes[] = {
- [USI_V2_NONE] = { .name = "none", .val = USI_V2_SW_CONF_NONE },
- [USI_V2_UART] = { .name = "uart", .val = USI_V2_SW_CONF_UART },
- [USI_V2_SPI] = { .name = "spi", .val = USI_V2_SW_CONF_SPI },
- [USI_V2_I2C] = { .name = "i2c", .val = USI_V2_SW_CONF_I2C },
+#define USI_MODES_MAX (USI_MODE_UART_I2C1 + 1)
+static const struct exynos_usi_mode exynos_usi_modes[][USI_MODES_MAX] = {
+ [USI_VER1] = {
+ [USI_MODE_NONE] = { .name = "none", .val = USI_V1_SW_CONF_NONE },
+ [USI_MODE_UART] = { .name = "uart", .val = USI_V1_SW_CONF_UART },
+ [USI_MODE_SPI] = { .name = "spi", .val = USI_V1_SW_CONF_SPI },
+ [USI_MODE_I2C] = { .name = "i2c", .val = USI_V1_SW_CONF_I2C0 },
+ [USI_MODE_I2C1] = { .name = "i2c1", .val = USI_V1_SW_CONF_I2C1 },
+ [USI_MODE_I2C0_1] = { .name = "i2c0_1", .val = USI_V1_SW_CONF_I2C0_1 },
+ [USI_MODE_UART_I2C1] = { .name = "uart_i2c1", .val = USI_V1_SW_CONF_UART_I2C1 },
+ }, [USI_VER2] = {
+ [USI_MODE_NONE] = { .name = "none", .val = USI_V2_SW_CONF_NONE },
+ [USI_MODE_UART] = { .name = "uart", .val = USI_V2_SW_CONF_UART },
+ [USI_MODE_SPI] = { .name = "spi", .val = USI_V2_SW_CONF_SPI },
+ [USI_MODE_I2C] = { .name = "i2c", .val = USI_V2_SW_CONF_I2C },
+ },
};
static const char * const exynos850_usi_clk_names[] = { "pclk", "ipclk" };
static const struct exynos_usi_variant exynos850_usi_data = {
.ver = USI_VER2,
.sw_conf_mask = USI_V2_SW_CONF_MASK,
- .min_mode = USI_V2_NONE,
- .max_mode = USI_V2_I2C,
+ .min_mode = USI_MODE_NONE,
+ .max_mode = USI_MODE_I2C,
+ .num_clks = ARRAY_SIZE(exynos850_usi_clk_names),
+ .clk_names = exynos850_usi_clk_names,
+};
+
+static const struct exynos_usi_variant exynos8895_usi_data = {
+ .ver = USI_VER1,
+ .sw_conf_mask = USI_V1_SW_CONF_MASK,
+ .min_mode = USI_MODE_NONE,
+ .max_mode = USI_MODE_UART_I2C1,
.num_clks = ARRAY_SIZE(exynos850_usi_clk_names),
.clk_names = exynos850_usi_clk_names,
};
@@ -88,6 +121,10 @@ static const struct of_device_id exynos_usi_dt_match[] = {
.compatible = "samsung,exynos850-usi",
.data = &exynos850_usi_data,
},
+ {
+ .compatible = "samsung,exynos8895-usi",
+ .data = &exynos8895_usi_data,
+ },
{ } /* sentinel */
};
MODULE_DEVICE_TABLE(of, exynos_usi_dt_match);
@@ -109,14 +146,15 @@ static int exynos_usi_set_sw_conf(struct exynos_usi *usi, size_t mode)
if (mode < usi->data->min_mode || mode > usi->data->max_mode)
return -EINVAL;
- val = exynos_usi_modes[mode].val;
+ val = exynos_usi_modes[usi->data->ver][mode].val;
ret = regmap_update_bits(usi->sysreg, usi->sw_conf,
usi->data->sw_conf_mask, val);
if (ret)
return ret;
usi->mode = mode;
- dev_dbg(usi->dev, "protocol: %s\n", exynos_usi_modes[usi->mode].name);
+ dev_dbg(usi->dev, "protocol: %s\n",
+ exynos_usi_modes[usi->data->ver][usi->mode].name);
return 0;
}
@@ -160,6 +198,30 @@ static int exynos_usi_enable(const struct exynos_usi *usi)
return ret;
}
+/**
+ * exynos_usi_disable - Disable USI block
+ * @usi: USI driver object
+ *
+ * USI IP-core needs the reset flag cleared in order to function. This
+ * routine disables the USI block by setting the reset flag. It also disables
+ * HWACG behavior. It should be performed on removal of the device.
+ */
+static void exynos_usi_disable(const struct exynos_usi *usi)
+{
+ u32 val;
+
+ /* Make sure that we've stopped providing the clock to USI IP */
+ val = readl(usi->regs + USI_OPTION);
+ val &= ~USI_OPTION_CLKREQ_ON;
+ val |= ~USI_OPTION_CLKSTOP_ON;
+ writel(val, usi->regs + USI_OPTION);
+
+ /* Set USI block state to reset */
+ val = readl(usi->regs + USI_CON);
+ val |= USI_CON_RESET;
+ writel(val, usi->regs + USI_CON);
+}
+
static int exynos_usi_configure(struct exynos_usi *usi)
{
int ret;
@@ -169,9 +231,12 @@ static int exynos_usi_configure(struct exynos_usi *usi)
return ret;
if (usi->data->ver == USI_VER2)
- return exynos_usi_enable(usi);
+ ret = exynos_usi_enable(usi);
+ else
+ ret = clk_bulk_prepare_enable(usi->data->num_clks,
+ usi->clks);
- return 0;
+ return ret;
}
static int exynos_usi_parse_dt(struct device_node *np, struct exynos_usi *usi)
@@ -253,10 +318,26 @@ static int exynos_usi_probe(struct platform_device *pdev)
ret = exynos_usi_configure(usi);
if (ret)
- return ret;
+ goto fail_probe;
/* Make it possible to embed protocol nodes into USI np */
return of_platform_populate(np, NULL, NULL, dev);
+
+fail_probe:
+ if (usi->data->ver != USI_VER2)
+ clk_bulk_disable_unprepare(usi->data->num_clks, usi->clks);
+
+ return ret;
+}
+
+static void exynos_usi_remove(struct platform_device *pdev)
+{
+ struct exynos_usi *usi = platform_get_drvdata(pdev);
+
+ if (usi->data->ver == USI_VER2)
+ exynos_usi_disable(usi);
+ else
+ clk_bulk_disable_unprepare(usi->data->num_clks, usi->clks);
}
static int __maybe_unused exynos_usi_resume_noirq(struct device *dev)
@@ -277,6 +358,7 @@ static struct platform_driver exynos_usi_driver = {
.of_match_table = exynos_usi_dt_match,
},
.probe = exynos_usi_probe,
+ .remove = exynos_usi_remove,
};
module_platform_driver(exynos_usi_driver);
USIv1 IP-core is found on some ARM64 Exynos SoCs (like Exynos8895) and provides selectable serial protocols (one of: HSI2C0, HSI2C1, HSI2C0_1, SPI, UART, UART_HSI2C1). USIv1, unlike USIv2, doesn't have any known register map. Underlying protocols that it implements have no offset, like with Exynos850. Desired protocol can be chosen via SW_CONF register from System Register block of the same domain as USI. In order to select a particular protocol, the protocol has to be selected via the System Register. Unlike USIv2, there's no need for any setup before the given protocol becomes accessible apart from enabling the APB clock and the protocol operating clock. Modify the existing driver in order to allow USIv1 instances in Exynos8895 to probe and set their protocol. While we're at it, make use of the new mode constants in place of the old ones and add a removal routine. Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com> --- drivers/soc/samsung/exynos-usi.c | 108 +++++++++++++++++++++++++++---- 1 file changed, 95 insertions(+), 13 deletions(-)