drivers/i2c/busses/i2c-mt65xx.c

Source file repositories/reference/linux-study-clean/drivers/i2c/busses/i2c-mt65xx.c

File Facts

System
Linux kernel
Corpus path
drivers/i2c/busses/i2c-mt65xx.c
Extension
.c
Size
43021 bytes
Lines
1574
Domain
Driver Families
Bucket
drivers/i2c
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mtk_i2c_compatible {
	const struct i2c_adapter_quirks *quirks;
	const u16 *regs;
	unsigned char pmic_i2c: 1;
	unsigned char dcm: 1;
	unsigned char auto_restart: 1;
	unsigned char aux_len_reg: 1;
	unsigned char timing_adjust: 1;
	unsigned char dma_sync: 1;
	unsigned char ltiming_adjust: 1;
	unsigned char apdma_sync: 1;
	unsigned char max_dma_support;
};

struct mtk_i2c_ac_timing {
	u16 htiming;
	u16 ltiming;
	u16 hs;
	u16 ext;
	u16 inter_clk_div;
	u16 scl_hl_ratio;
	u16 hs_scl_hl_ratio;
	u16 sta_stop;
	u16 hs_sta_stop;
	u16 sda_timing;
};

struct mtk_i2c {
	struct i2c_adapter adap;	/* i2c host adapter */
	struct device *dev;
	struct completion msg_complete;
	struct i2c_timings timing_info;

	/* set in i2c probe */
	void __iomem *base;		/* i2c base addr */
	void __iomem *pdmabase;		/* dma base address*/
	struct clk_bulk_data clocks[I2C_MT65XX_CLK_MAX]; /* clocks for i2c */
	bool have_pmic;			/* can use i2c pins from PMIC */
	bool use_push_pull;		/* IO config push-pull mode */

	u16 irq_stat;			/* interrupt status */
	unsigned int clk_src_div;
	unsigned int speed_hz;		/* The speed in transfer */
	enum mtk_trans_op op;
	u16 timing_reg;
	u16 high_speed_reg;
	u16 ltiming_reg;
	unsigned char auto_restart;
	bool ignore_restart_irq;
	struct mtk_i2c_ac_timing ac_timing;
	const struct mtk_i2c_compatible *dev_comp;
};

/**
 * struct i2c_spec_values:
 * @min_low_ns: min LOW period of the SCL clock
 * @min_su_sta_ns: min set-up time for a repeated START condition
 * @max_hd_dat_ns: max data hold time
 * @min_su_dat_ns: min data set-up time
 */
struct i2c_spec_values {
	unsigned int min_low_ns;
	unsigned int min_su_sta_ns;
	unsigned int max_hd_dat_ns;
	unsigned int min_su_dat_ns;
};

static const struct i2c_spec_values standard_mode_spec = {
	.min_low_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
	.min_su_sta_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
	.max_hd_dat_ns = 3450 - I2C_STANDARD_MODE_BUFFER,
	.min_su_dat_ns = 250 + I2C_STANDARD_MODE_BUFFER,
};

static const struct i2c_spec_values fast_mode_spec = {
	.min_low_ns = 1300 + I2C_FAST_MODE_BUFFER,
	.min_su_sta_ns = 600 + I2C_FAST_MODE_BUFFER,
	.max_hd_dat_ns = 900 - I2C_FAST_MODE_BUFFER,
	.min_su_dat_ns = 100 + I2C_FAST_MODE_BUFFER,
};

static const struct i2c_spec_values fast_mode_plus_spec = {
	.min_low_ns = 500 + I2C_FAST_MODE_PLUS_BUFFER,
	.min_su_sta_ns = 260 + I2C_FAST_MODE_PLUS_BUFFER,
	.max_hd_dat_ns = 400 - I2C_FAST_MODE_PLUS_BUFFER,
	.min_su_dat_ns = 50 + I2C_FAST_MODE_PLUS_BUFFER,
};

static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
	.flags = I2C_AQ_COMB_WRITE_THEN_READ,

Annotation

Implementation Notes