[PATCH v2 11/11] i2c: npcm: Support NPCM845

Tyrone Ting
2022-02-20T03:57:52Z

From: Tyrone Ting <kfting@nuvoton.com>

Add NPCM8XX I2C support.
The NPCM8XX uses a similar i2c module as NPCM7XX.
The internal HW FIFO is larger in NPCM8XX.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
---
drivers/i2c/busses/Kconfig | 8 +--
drivers/i2c/busses/Makefile | 2 +-
drivers/i2c/busses/i2c-npcm7xx.c | 87 ++++++++++++++++++++++----------
3 files changed, 66 insertions(+), 31 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 42da31c1ab70..ab9ee2de5e00 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -817,13 +817,13 @@ config I2C_NOMADIK
I2C interface from ST-Ericsson's Nomadik and Ux500 architectures,
as well as the STA2X11 PCIe I/O HUB.

-config I2C_NPCM7XX
+config I2C_NPCM
tristate "Nuvoton I2C Controller"
- depends on ARCH_NPCM7XX || COMPILE_TEST
+ depends on ARCH_NPCM || COMPILE_TEST
help
If you say yes to this option, support will be included for the
- Nuvoton I2C controller, which is available on the NPCM7xx BMC
- controller.
+ Nuvoton I2C controller, which is available on the NPCM BMC
+ controllers.
Driver can also support slave mode (select I2C_SLAVE).

config I2C_OCORES
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 1d00dce77098..01fdf74a5565 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -80,7 +80,7 @@ obj-$(CONFIG_I2C_MT7621) += i2c-mt7621.o
obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o
obj-$(CONFIG_I2C_MXS) += i2c-mxs.o
obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
-obj-$(CONFIG_I2C_NPCM7XX) += i2c-npcm7xx.o
+obj-$(CONFIG_I2C_NPCM) += i2c-npcm7xx.o
obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o
obj-$(CONFIG_I2C_OMAP) += i2c-omap.o
obj-$(CONFIG_I2C_OWL) += i2c-owl.o
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 2cbf9c679aed..b281e0424e3e 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -17,6 +17,7 @@
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

@@ -91,7 +92,7 @@ enum i2c_addr {

/* init register and default value required to enable module */
#define NPCM_I2CSEGCTL 0xE4
-#define NPCM_I2CSEGCTL_INIT_VAL 0x0333F000
+#define NPCM_I2CSEGCTL_INIT_VAL bus->data->segctl_init_val

/* Common regs */
#define NPCM_I2CSDA 0x00
@@ -228,8 +229,7 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define NPCM_I2CFIF_CTS_CLR_FIFO BIT(6)
#define NPCM_I2CFIF_CTS_SLVRSTR BIT(7)

-/* NPCM_I2CTXF_CTL reg fields */
-#define NPCM_I2CTXF_CTL_TX_THR GENMASK(4, 0)
+/* NPCM_I2CTXF_CTL reg field */
#define NPCM_I2CTXF_CTL_THR_TXIE BIT(6)

/* NPCM_I2CT_OUT reg fields */
@@ -238,22 +238,22 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define NPCM_I2CT_OUT_T_OUTST BIT(7)

/* NPCM_I2CTXF_STS reg fields */
-#define NPCM_I2CTXF_STS_TX_BYTES GENMASK(4, 0)
+#define NPCM_I2CTXF_STS_TX_BYTES bus->data->txf_sts_tx_bytes
#define NPCM_I2CTXF_STS_TX_THST BIT(6)

/* NPCM_I2CRXF_STS reg fields */
-#define NPCM_I2CRXF_STS_RX_BYTES GENMASK(4, 0)
+#define NPCM_I2CRXF_STS_RX_BYTES bus->data->rxf_sts_rx_bytes
#define NPCM_I2CRXF_STS_RX_THST BIT(6)

/* NPCM_I2CFIF_CTL reg fields */
#define NPCM_I2CFIF_CTL_FIFO_EN BIT(4)

/* NPCM_I2CRXF_CTL reg fields */
-#define NPCM_I2CRXF_CTL_RX_THR GENMASK(4, 0)
-#define NPCM_I2CRXF_CTL_LAST_PEC BIT(5)
+#define NPCM_I2CRXF_CTL_LAST_PEC bus->data->rxf_ctl_last_pec
#define NPCM_I2CRXF_CTL_THR_RXIE BIT(6)

-#define I2C_HW_FIFO_SIZE 16
+#define MAX_I2C_HW_FIFO_SIZE 32
+#define I2C_HW_FIFO_SIZE bus->data->fifo_size

/* I2C_VER reg fields */
#define I2C_VER_VERSION GENMASK(6, 0)
@@ -270,11 +270,36 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define I2C_FREQ_MIN_HZ 10000
#define I2C_FREQ_MAX_HZ I2C_MAX_FAST_MODE_PLUS_FREQ

+struct npcm_i2c_data {
+ u8 fifo_size;
+ u32 segctl_init_val;
+ u8 txf_sts_tx_bytes;
+ u8 rxf_sts_rx_bytes;
+ u8 rxf_ctl_last_pec;
+};
+
+static const struct npcm_i2c_data npxm7xx_i2c_data = {
+ .fifo_size = 16,
+ .segctl_init_val = 0x0333F000,
+ .txf_sts_tx_bytes = GENMASK(4, 0),
+ .rxf_sts_rx_bytes = GENMASK(4, 0),
+ .rxf_ctl_last_pec = BIT(5)
+};
+
+static const struct npcm_i2c_data npxm8xx_i2c_data = {
+ .fifo_size = 32,
+ .segctl_init_val = 0x9333F000,
+ .txf_sts_tx_bytes = GENMASK(5, 0),
+ .rxf_sts_rx_bytes = GENMASK(5, 0),
+ .rxf_ctl_last_pec = BIT(7)
+};
+
/* Status of one I2C module */
struct npcm_i2c {
struct i2c_adapter adap;
struct device *dev;
unsigned char __iomem *reg;
+ const struct npcm_i2c_data *data;
spinlock_t lock; /* IRQ synchronization */
struct completion cmd_complete;
int cmd_err;
@@ -307,8 +332,8 @@ struct npcm_i2c {
int slv_rd_ind;
int slv_wr_size;
int slv_wr_ind;
- u8 slv_rd_buf[I2C_HW_FIFO_SIZE];
- u8 slv_wr_buf[I2C_HW_FIFO_SIZE];
+ u8 slv_rd_buf[MAX_I2C_HW_FIFO_SIZE];
+ u8 slv_wr_buf[MAX_I2C_HW_FIFO_SIZE];
#endif
struct dentry *debugfs; /* debugfs device directory */
u64 ber_cnt;
@@ -743,11 +768,11 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus)
{
if (bus->operation == I2C_WRITE_OPER)
- return FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
- ioread8(bus->reg + NPCM_I2CTXF_STS));
+ return (NPCM_I2CTXF_STS_TX_BYTES &
+ ioread8(bus->reg + NPCM_I2CTXF_STS));
if (bus->operation == I2C_READ_OPER)
- return FIELD_GET(NPCM_I2CRXF_STS_RX_BYTES,
- ioread8(bus->reg + NPCM_I2CRXF_STS));
+ return (NPCM_I2CRXF_STS_RX_BYTES &
+ ioread8(bus->reg + NPCM_I2CRXF_STS));
return 0;
}

@@ -882,10 +907,10 @@ static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes)
while (max_bytes-- && I2C_HW_FIFO_SIZE != npcm_i2c_fifo_usage(bus)) {
if (bus->slv_wr_size <= 0)
break;
- bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_wr_ind = bus->slv_wr_ind & (I2C_HW_FIFO_SIZE - 1);
npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]);
bus->slv_wr_ind++;
- bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_wr_ind = bus->slv_wr_ind & (I2C_HW_FIFO_SIZE - 1);
bus->slv_wr_size--;
}
}
@@ -900,7 +925,7 @@ static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo)
while (bytes_in_fifo--) {
data = npcm_i2c_rd_byte(bus);

- bus->slv_rd_ind = bus->slv_rd_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_rd_ind = bus->slv_rd_ind & (I2C_HW_FIFO_SIZE - 1);
bus->slv_rd_buf[bus->slv_rd_ind] = data;
bus->slv_rd_ind++;

@@ -927,7 +952,7 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
} else {
i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
}
- ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
+ ind = (bus->slv_wr_ind + bus->slv_wr_size) & (I2C_HW_FIFO_SIZE - 1);
bus->slv_wr_buf[ind] = value;
bus->slv_wr_size++;
}
@@ -999,8 +1024,8 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
{
int left_in_fifo;

- left_in_fifo = FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
- ioread8(bus->reg + NPCM_I2CTXF_STS));
+ left_in_fifo = (NPCM_I2CTXF_STS_TX_BYTES &
+ ioread8(bus->reg + NPCM_I2CTXF_STS));

/* fifo already full: */
if (left_in_fifo >= I2C_HW_FIFO_SIZE ||
@@ -2265,12 +2290,21 @@ static void npcm_i2c_init_debugfs(struct platform_device *pdev,
bus->debugfs = d;
}

+static const struct of_device_id npcm_i2c_bus_of_table[] = {
+ { .compatible = "nuvoton,npcm750-i2c", .data = &npxm7xx_i2c_data },
+ { .compatible = "nuvoton,npcm845-i2c", .data = &npxm8xx_i2c_data },
+ {}
+};
+MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table);
+
static int npcm_i2c_probe_bus(struct platform_device *pdev)
{
struct npcm_i2c *bus;
struct i2c_adapter *adap;
struct clk *i2c_clk;
static struct regmap *gcr_regmap;
+ struct device *dev = &pdev->dev;
+ const struct of_device_id *match;
int irq;
int ret;
struct device_node *np = pdev->dev.of_node;
@@ -2281,6 +2315,13 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)

bus->dev = &pdev->dev;

+ match = of_match_device(npcm_i2c_bus_of_table, dev);
+ if (!match) {
+ dev_err(dev, "OF data missing\n");
+ return -EINVAL;
+ }
+ bus->data = match->data;
+
bus->num = of_alias_get_id(pdev->dev.of_node, "i2c");
/* core clk must be acquired to calculate module timing settings */
i2c_clk = devm_clk_get(&pdev->dev, NULL);
@@ -2352,12 +2393,6 @@ static int npcm_i2c_remove_bus(struct platform_device *pdev)
return 0;
}

-static const struct of_device_id npcm_i2c_bus_of_table[] = {
- { .compatible = "nuvoton,npcm750-i2c", },
- {}
-};
-MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table);
-
static struct platform_driver npcm_i2c_bus_driver = {
.probe = npcm_i2c_probe_bus,
.remove = npcm_i2c_remove_bus,
--
2.17.1