Commit e27e2160 authored by Michael Buesch's avatar Michael Buesch Committed by Alexandre Belloni
Browse files

rtc: rv3029: Add device tree property for trickle charger 



The trickle charger resistor can be enabled via device tree
property trickle-resistor-ohms.

Signed-off-by: default avatarMichael Buesch <m@bues.ch>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
parent a7f6e287

drivers/rtc/rtc-rv3029c2.c

+103 −3
Original line number Diff line number Diff line
@@ -10,9 +10,6 @@ 
 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * NOTE: Currently this driver only supports the bare minimum for read

 * and write the RTC and alarms. The extra features provided by this chip

 * (trickle charger, eeprom, T° compensation) are unavailable.

 */



#include <linux/module.h>
@@ -528,6 +525,107 @@ static int rv3029_rtc_set_time(struct device *dev, struct rtc_time *tm) 
	return rv3029_i2c_set_time(to_i2c_client(dev), tm);

}



static const struct rv3029_trickle_tab_elem {

	u32 r;		/* resistance in ohms */

	u8 conf;	/* trickle config bits */

} rv3029_trickle_tab[] = {

	{

		.r	= 1076,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |

			  RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,

	}, {

		.r	= 1091,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |

			  RV3029_TRICKLE_20K,

	}, {

		.r	= 1137,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |

			  RV3029_TRICKLE_80K,

	}, {

		.r	= 1154,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,

	}, {

		.r	= 1371,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |

			  RV3029_TRICKLE_80K,

	}, {

		.r	= 1395,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,

	}, {

		.r	= 1472,

		.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,

	}, {

		.r	= 1500,

		.conf	= RV3029_TRICKLE_1K,

	}, {

		.r	= 3810,

		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |

			  RV3029_TRICKLE_80K,

	}, {

		.r	= 4000,

		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,

	}, {

		.r	= 4706,

		.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,

	}, {

		.r	= 5000,

		.conf	= RV3029_TRICKLE_5K,

	}, {

		.r	= 16000,

		.conf	= RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,

	}, {

		.r	= 20000,

		.conf	= RV3029_TRICKLE_20K,

	}, {

		.r	= 80000,

		.conf	= RV3029_TRICKLE_80K,

	},

};



static void rv3029_trickle_config(struct i2c_client *client)

{

	struct device_node *of_node = client->dev.of_node;

	const struct rv3029_trickle_tab_elem *elem;

	int i, err;

	u32 ohms;

	u8 eectrl;



	if (!of_node)

		return;



	/* Configure the trickle charger. */

	err = rv3029_eeprom_read(client, RV3029_CONTROL_E2P_EECTRL,

				 &eectrl, 1);

	if (err < 0) {

		dev_err(&client->dev,

			"Failed to read trickle charger config\n");

		return;

	}

	err = of_property_read_u32(of_node, "trickle-resistor-ohms", &ohms);

	if (err) {

		/* Disable trickle charger. */

		eectrl &= ~RV3029_TRICKLE_MASK;

	} else {

		/* Enable trickle charger. */

		for (i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++) {

			elem = &rv3029_trickle_tab[i];

			if (elem->r >= ohms)

				break;

		}

		eectrl &= ~RV3029_TRICKLE_MASK;

		eectrl |= elem->conf;

		dev_info(&client->dev,

			 "Trickle charger enabled at %d ohms resistance.\n",

			 elem->r);

	}

	err = rv3029_eeprom_write(client, RV3029_CONTROL_E2P_EECTRL,

				  &eectrl, 1);

	if (err < 0) {

		dev_err(&client->dev,

			"Failed to write trickle charger config\n");

	}

}



static const struct rtc_class_ops rv3029_rtc_ops = {

	.read_time	= rv3029_rtc_read_time,

	.set_time	= rv3029_rtc_set_time,
@@ -558,6 +656,8 @@ static int rv3029_probe(struct i2c_client *client, 
		return rc;

	}



	rv3029_trickle_config(client);



	rtc = devm_rtc_device_register(&client->dev, client->name,

				       &rv3029_rtc_ops, THIS_MODULE);