The EC switches three power lines for the display controller:
2.5V for the self-refresh frame SDRAM
3.3V for the digital I/O pins
1.8V for the controller core and also the DETTL display interface
pins.
Note that all lines can be either disabled or enabled together.
Signed-off-by: Lubomir Rintel <lkund...@v3.sk>
---
drivers/platform/olpc/olpc-ec.c | 92 +++++++++++++++++++++++----------
1 file changed, 65 insertions(+), 27 deletions(-)
diff --git a/drivers/platform/olpc/olpc-ec.c b/drivers/platform/olpc/olpc-ec.c
index 72dbbea0005c5..2ab57ffb3d63e 100644
--- a/drivers/platform/olpc/olpc-ec.c
+++ b/drivers/platform/olpc/olpc-ec.c
@@ -5,6 +5,7 @@
* Author: Andres Salomon <dilin...@queued.net>
*
* Copyright (C) 2011-2012 One Laptop per Child Foundation.
+ * Copyright (C) 2020 Lubomir Rintel <lkund...@v3.sk>
*/
#include <linux/completion.h>
#include <linux/debugfs.h>
@@ -17,6 +18,7 @@
#include <linux/list.h>
#include <linux/regulator/driver.h>
#include <linux/olpc-ec.h>
+#include <linux/of.h>
struct ec_cmd_desc {
u8 cmd;
@@ -37,7 +39,7 @@ struct olpc_ec_priv {
struct mutex cmd_lock;
/* DCON regulator */
- bool dcon_enabled;
+ unsigned int dcon_enable_count;
/* Pending EC commands */
struct list_head cmd_q;
@@ -352,38 +354,45 @@ static struct dentry *olpc_ec_setup_debugfs(void)
static int olpc_ec_set_dcon_power(struct olpc_ec_priv *ec, bool state)
{
unsigned char ec_byte = state;
- int ret;
- if (ec->dcon_enabled == state)
- return 0;
-
- ret = olpc_ec_cmd(EC_DCON_POWER_MODE, &ec_byte, 1, NULL, 0);
- if (ret)
- return ret;
-
- ec->dcon_enabled = state;
- return 0;
+ return olpc_ec_cmd(EC_DCON_POWER_MODE, &ec_byte, 1, NULL, 0);
}
static int dcon_regulator_enable(struct regulator_dev *rdev)
{
struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
+ int ret;
- return olpc_ec_set_dcon_power(ec, true);
+ if (ec->dcon_enable_count == 0) {
+ ret = olpc_ec_set_dcon_power(ec, true);
+ if (ret)
+ return ret;
+ }
+
+ ec->dcon_enable_count++;
+ return 0;
}
static int dcon_regulator_disable(struct regulator_dev *rdev)
{
struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
+ int ret;
- return olpc_ec_set_dcon_power(ec, false);
+ if (ec->dcon_enable_count == 1) {
+ ret = olpc_ec_set_dcon_power(ec, false);
+ if (ret)
+ return ret;
+ }
+
+ ec->dcon_enable_count--;
+ return 0;
}
static int dcon_regulator_is_enabled(struct regulator_dev *rdev)
{
struct olpc_ec_priv *ec = rdev_get_drvdata(rdev);
- return ec->dcon_enabled ? 1 : 0;
+ return ec->dcon_enable_count ? 1 : 0;
}
static struct regulator_ops dcon_regulator_ops = {
@@ -392,13 +401,36 @@ static struct regulator_ops dcon_regulator_ops = {
.is_enabled = dcon_regulator_is_enabled,
};
-static const struct regulator_desc dcon_desc = {
- .name = "dcon",
- .id = 0,
- .ops = &dcon_regulator_ops,
- .type = REGULATOR_VOLTAGE,
- .owner = THIS_MODULE,
- .enable_time = 25000,
+static const struct regulator_desc regulators[] = {
+ {
+ .name = "v2_5_dcon",
+ .of_match = of_match_ptr("v2_5_dcon"),
+ .regulators_node = of_match_ptr("regulators"),
+ .n_voltages = 1,
+ .fixed_uV = 2500000,
+ .ops = &dcon_regulator_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ }, {
+ .name = "v3_3_dcon",
+ .of_match = of_match_ptr("v3_3_dcon"),
+ .regulators_node = of_match_ptr("regulators"),
+ .n_voltages = 1,
+ .fixed_uV = 3300000,
+ .ops = &dcon_regulator_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ }, {
+ .name = "v1_8_dcon",
+ .of_match = of_match_ptr("v1_8_dcon"),
+ .regulators_node = of_match_ptr("regulators"),
+ .n_voltages = 1,
+ .fixed_uV = 1800000,
+ .ops = &dcon_regulator_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ .enable_time = 25000,
+ }
};
static int olpc_ec_probe(struct platform_device *pdev)
@@ -406,6 +438,7 @@ static int olpc_ec_probe(struct platform_device *pdev)
struct olpc_ec_priv *ec;
struct regulator_config config = { };
struct regulator_dev *regulator;
+ int i;
int err;
if (!ec_driver)
@@ -432,12 +465,17 @@ static int olpc_ec_probe(struct platform_device *pdev)
config.dev = pdev->dev.parent;
config.driver_data = ec;
- ec->dcon_enabled = true;
- regulator = devm_regulator_register(&pdev->dev, &dcon_desc, &config);
- if (IS_ERR(regulator)) {
- dev_err(&pdev->dev, "failed to register DCON regulator\n");
- err = PTR_ERR(regulator);
- goto error;
+ ec->dcon_enable_count = ARRAY_SIZE(regulators);
+
+ for (i = 0; i < ARRAY_SIZE(regulators); i++) {
+ regulator = devm_regulator_register(&pdev->dev,
+ ®ulators[i], &config);
+ if (IS_ERR(regulator)) {
+ dev_err(&pdev->dev, "failed to register %s regulator\n",
+ regulators[i].name);
+ err = PTR_ERR(regulator);
+ goto error;
+ }
}
ec->dbgfs_dir = olpc_ec_setup_debugfs();
--
2.28.0
