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Commit 9c95bb6f authored by Michael Arndt's avatar Michael Arndt Committed by Greg Kroah-Hartman
Browse files

w1: ds2482: Added 1-Wire pull-up support to the driver 



Signed-off-by: default avatarMichael Arndt <michael@scriptkiller.de>
Acked-by: default avatarEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent def1820d

drivers/w1/masters/ds2482.c

+45 −6
Original line number Diff line number Diff line
@@ -51,10 +51,10 @@ 
 * The top 4 bits always read 0.

 * To write, the top nibble must be the 1's compl. of the low nibble.

 */

#define DS2482_REG_CFG_1WS		0x08

#define DS2482_REG_CFG_SPU		0x04

#define DS2482_REG_CFG_PPM		0x02

#define DS2482_REG_CFG_APU		0x01

#define DS2482_REG_CFG_1WS		0x08	/* 1-wire speed */

#define DS2482_REG_CFG_SPU		0x04	/* strong pull-up */

#define DS2482_REG_CFG_PPM		0x02	/* presence pulse masking */

#define DS2482_REG_CFG_APU		0x01	/* active pull-up */





/**
@@ -131,6 +131,17 @@ struct ds2482_data { 
};





/**

 * Helper to calculate values for configuration register

 * @param conf the raw config value

 * @return the value w/ complements that can be written to register

 */

static inline u8 ds2482_calculate_config(u8 conf)

{

	return conf | ((~conf & 0x0f) << 4);

}





/**

 * Sets the read pointer.

 * @param pdev		The ds2482 client pointer
@@ -399,7 +410,7 @@ static u8 ds2482_w1_reset_bus(void *data) 
		/* If the chip did reset since detect, re-config it */

		if (err & DS2482_REG_STS_RST)

			ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,

					     0xF0);

					     ds2482_calculate_config(0x00));

	}



	mutex_unlock(&pdev->access_lock);
@@ -407,6 +418,32 @@ static u8 ds2482_w1_reset_bus(void *data) 
	return retval;

}



static u8 ds2482_w1_set_pullup(void *data, int delay)

{

	struct ds2482_w1_chan *pchan = data;

	struct ds2482_data    *pdev = pchan->pdev;

	u8 retval = 1;



	/* if delay is non-zero activate the pullup,

	 * the strong pullup will be automatically deactivated

	 * by the master, so do not explicitly deactive it

	 */

	if (delay) {

		/* both waits are crucial, otherwise devices might not be

		 * powered long enough, causing e.g. a w1_therm sensor to

		 * provide wrong conversion results

		 */

		ds2482_wait_1wire_idle(pdev);

		/* note: it seems like both SPU and APU have to be set! */

		retval = ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,

			ds2482_calculate_config(DS2482_REG_CFG_SPU |

						DS2482_REG_CFG_APU));

		ds2482_wait_1wire_idle(pdev);

	}



	return retval;

}





static int ds2482_probe(struct i2c_client *client,

			const struct i2c_device_id *id)
@@ -452,7 +489,8 @@ static int ds2482_probe(struct i2c_client *client, 
		data->w1_count = 8;



	/* Set all config items to 0 (off) */

	ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG, 0xF0);

	ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG,

		ds2482_calculate_config(0x00));



	mutex_init(&data->access_lock);
@@ -468,6 +506,7 @@ static int ds2482_probe(struct i2c_client *client, 
		data->w1_ch[idx].w1_bm.touch_bit  = ds2482_w1_touch_bit;

		data->w1_ch[idx].w1_bm.triplet    = ds2482_w1_triplet;

		data->w1_ch[idx].w1_bm.reset_bus  = ds2482_w1_reset_bus;

		data->w1_ch[idx].w1_bm.set_pullup = ds2482_w1_set_pullup;



		err = w1_add_master_device(&data->w1_ch[idx].w1_bm);

		if (err) {