42 int i2c_bitbang_configure(struct i2c_bitbang *context, uint32_t dev_config)  in i2c_bitbang_configure()  argument
52 		context->delays[T_LOW]  = NS_TO_SYS_CLOCK_HW_CYCLES(4700);  in i2c_bitbang_configure()
53 		context->delays[T_HIGH] = NS_TO_SYS_CLOCK_HW_CYCLES(4000);  in i2c_bitbang_configure()
56 		context->delays[T_LOW]  = NS_TO_SYS_CLOCK_HW_CYCLES(1300);  in i2c_bitbang_configure()
57 		context->delays[T_HIGH] = NS_TO_SYS_CLOCK_HW_CYCLES(600);  in i2c_bitbang_configure()
63 	context->dev_config = dev_config;  in i2c_bitbang_configure()
68 int i2c_bitbang_get_config(struct i2c_bitbang *context, uint32_t *config)  in i2c_bitbang_get_config()  argument
70 	if (context->dev_config == 0) {  in i2c_bitbang_get_config()
74 	*config = context->dev_config;  in i2c_bitbang_get_config()
79 static void i2c_set_scl(struct i2c_bitbang *context, int state)  in i2c_set_scl()  argument
81 	context->io->set_scl(context->io_context, state);  in i2c_set_scl()
84 static void i2c_set_sda(struct i2c_bitbang *context, int state)  in i2c_set_sda()  argument
86 	context->io->set_sda(context->io_context, state);  in i2c_set_sda()
89 static int i2c_get_sda(struct i2c_bitbang *context)  in i2c_get_sda()  argument
91 	return context->io->get_sda(context->io_context);  in i2c_get_sda()
103 static void i2c_start(struct i2c_bitbang *context)  in i2c_start()  argument
105 	if (!i2c_get_sda(context)) {  in i2c_start()
110 		i2c_set_scl(context, 0);  in i2c_start()
111 		i2c_delay(context->delays[T_LOW]);  in i2c_start()
112 		i2c_set_scl(context, 1);  in i2c_start()
113 		i2c_delay(context->delays[T_SU_STA]);  in i2c_start()
115 	i2c_set_sda(context, 0);  in i2c_start()
116 	i2c_delay(context->delays[T_HD_STA]);  in i2c_start()
118 	i2c_set_scl(context, 0);  in i2c_start()
119 	i2c_delay(context->delays[T_LOW]);  in i2c_start()
122 static void i2c_repeated_start(struct i2c_bitbang *context)  in i2c_repeated_start()  argument
124 	i2c_set_sda(context, 1);  in i2c_repeated_start()
125 	i2c_set_scl(context, 1);  in i2c_repeated_start()
126 	i2c_delay(context->delays[T_HIGH]);  in i2c_repeated_start()
128 	i2c_delay(context->delays[T_SU_STA]);  in i2c_repeated_start()
129 	i2c_start(context);  in i2c_repeated_start()
132 static void i2c_stop(struct i2c_bitbang *context)  in i2c_stop()  argument
134 	i2c_set_sda(context, 0);  in i2c_stop()
135 	i2c_delay(context->delays[T_LOW]);  in i2c_stop()
137 	i2c_set_scl(context, 1);  in i2c_stop()
138 	i2c_delay(context->delays[T_HIGH]);  in i2c_stop()
140 	i2c_delay(context->delays[T_SU_STP]);  in i2c_stop()
141 	i2c_set_sda(context, 1);  in i2c_stop()
142 	i2c_delay(context->delays[T_BUF]); /* In case we start again too soon */  in i2c_stop()
145 static void i2c_write_bit(struct i2c_bitbang *context, int bit)  in i2c_write_bit()  argument
148 	i2c_set_sda(context, bit);  in i2c_write_bit()
149 	i2c_set_scl(context, 1);  in i2c_write_bit()
150 	i2c_delay(context->delays[T_HIGH]);  in i2c_write_bit()
151 	i2c_set_scl(context, 0);  in i2c_write_bit()
152 	i2c_delay(context->delays[T_LOW]);  in i2c_write_bit()
155 static bool i2c_read_bit(struct i2c_bitbang *context)  in i2c_read_bit()  argument
160 	i2c_set_sda(context, 1); /* Stop driving low, so slave has control */  in i2c_read_bit()
162 	i2c_set_scl(context, 1);  in i2c_read_bit()
163 	i2c_delay(context->delays[T_HIGH]);  in i2c_read_bit()
165 	bit = i2c_get_sda(context);  in i2c_read_bit()
167 	i2c_set_scl(context, 0);  in i2c_read_bit()
168 	i2c_delay(context->delays[T_LOW]);  in i2c_read_bit()
172 static bool i2c_write_byte(struct i2c_bitbang *context, uint8_t byte)  in i2c_write_byte()  argument
177 		i2c_write_bit(context, byte & mask);  in i2c_write_byte()
181 	return !i2c_read_bit(context);  in i2c_write_byte()
184 static uint8_t i2c_read_byte(struct i2c_bitbang *context)  in i2c_read_byte()  argument
190 		byte |= i2c_read_bit(context);  in i2c_read_byte()
196 int i2c_bitbang_transfer(struct i2c_bitbang *context,  in i2c_bitbang_transfer()  argument
212 	i2c_set_scl(context, 1);  in i2c_bitbang_transfer()
218 			i2c_stop(context);  in i2c_bitbang_transfer()
226 			i2c_start(context);  in i2c_bitbang_transfer()
228 			i2c_repeated_start(context);  in i2c_bitbang_transfer()
239 			if (!i2c_write_byte(context, byte0)) {  in i2c_bitbang_transfer()
251 				*buf++ = i2c_read_byte(context);  in i2c_bitbang_transfer()
253 				i2c_write_bit(context, buf == buf_end);  in i2c_bitbang_transfer()
258 				if (!i2c_write_byte(context, *buf++)) {  in i2c_bitbang_transfer()
272 	i2c_stop(context);  in i2c_bitbang_transfer()
277 int i2c_bitbang_recover_bus(struct i2c_bitbang *context)  in i2c_bitbang_recover_bus()  argument
298 	i2c_start(context);  in i2c_bitbang_recover_bus()
302 		i2c_write_bit(context, 1);  in i2c_bitbang_recover_bus()
306 	i2c_repeated_start(context);  in i2c_bitbang_recover_bus()
307 	i2c_stop(context);  in i2c_bitbang_recover_bus()
310 	if (i2c_get_sda(context)) {  in i2c_bitbang_recover_bus()
317 void i2c_bitbang_init(struct i2c_bitbang *context,  in i2c_bitbang_init()  argument
320 	context->io = io;  in i2c_bitbang_init()
321 	context->io_context = io_context;  in i2c_bitbang_init()
322 	i2c_bitbang_configure(context, I2C_SPEED_STANDARD << I2C_SPEED_SHIFT);  in i2c_bitbang_init()