ARM: tegra: harmony: update PCI-e initialization sequence

On Harmony board PCI-e subsystem can be enabled only after certain
voltage regulators are on. One of the regulators is an internal
regulator on the PMIC and another one is controlled by a PMIC GPIO.
Addition of the voltage control to the Harmony PCI-e initialization
allows booting of kernel with CONFIG_TEGRA_PCI even if the PMIC driver
is not loaded. In this case the PCI-e initialization will fail
gracefully intead of hanging the system.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Mike Rapoport 2011-03-09 16:31:17 +02:00 committed by Olof Johansson
parent c4d9e4a0b9
commit ce005cf450
1 changed files with 23 additions and 1 deletions

View File

@ -27,13 +27,29 @@
#ifdef CONFIG_TEGRA_PCI
/* GPIO 3 of the PMIC */
#define EN_VDD_1V05_GPIO (TEGRA_NR_GPIOS + 2)
static int __init harmony_pcie_init(void)
{
struct regulator *regulator = NULL;
int err;
if (!machine_is_harmony())
return 0;
err = gpio_request(EN_VDD_1V05_GPIO, "EN_VDD_1V05");
if (err)
return err;
gpio_direction_output(EN_VDD_1V05_GPIO, 1);
regulator = regulator_get(NULL, "pex_clk");
if (IS_ERR_OR_NULL(regulator))
goto err_reg;
regulator_enable(regulator);
tegra_pinmux_set_tristate(TEGRA_PINGROUP_GPV, TEGRA_TRI_NORMAL);
tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXA, TEGRA_TRI_NORMAL);
tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXK, TEGRA_TRI_NORMAL);
@ -49,9 +65,15 @@ err_pcie:
tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXA, TEGRA_TRI_TRISTATE);
tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXK, TEGRA_TRI_TRISTATE);
regulator_disable(regulator);
regulator_put(regulator);
err_reg:
gpio_free(EN_VDD_1V05_GPIO);
return err;
}
subsys_initcall(harmony_pcie_init);
/* PCI should be initialized after I2C, mfd and regulators */
subsys_initcall_sync(harmony_pcie_init);
#endif