linux/drivers/scsi/ufs/ufshcd-pltfrm.c
Stanley Chu 24e2e7a19f scsi: ufs: Avoid runtime suspend possibly being blocked forever
UFS runtime suspend can be triggered after pm_runtime_enable() is invoked
in ufshcd_pltfrm_init(). However if the first runtime suspend is triggered
before binding ufs_hba structure to ufs device structure via
platform_set_drvdata(), then UFS runtime suspend will be no longer
triggered in the future because its dev->power.runtime_error was set in the
first triggering and does not have any chance to be cleared.

To be more clear, dev->power.runtime_error is set if hba is NULL in
ufshcd_runtime_suspend() which returns -EINVAL to rpm_callback() where
dev->power.runtime_error is set as -EINVAL. In this case, any future
rpm_suspend() for UFS device fails because rpm_check_suspend_allowed()
fails due to non-zero
dev->power.runtime_error.

To resolve this issue, make sure the first UFS runtime suspend get valid
"hba" in ufshcd_runtime_suspend(): Enable UFS runtime PM only after hba is
successfully bound to UFS device structure.

Fixes: 62694735ca ([SCSI] ufs: Add runtime PM support for UFS host controller driver)
Cc: stable@vger.kernel.org
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-06-18 22:50:25 -04:00

460 lines
12 KiB
C

/*
* Universal Flash Storage Host controller Platform bus based glue driver
*
* This code is based on drivers/scsi/ufs/ufshcd-pltfrm.c
* Copyright (C) 2011-2013 Samsung India Software Operations
*
* Authors:
* Santosh Yaraganavi <santosh.sy@samsung.com>
* Vinayak Holikatti <h.vinayak@samsung.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* See the COPYING file in the top-level directory or visit
* <http://www.gnu.org/licenses/gpl-2.0.html>
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* This program is provided "AS IS" and "WITH ALL FAULTS" and
* without warranty of any kind. You are solely responsible for
* determining the appropriateness of using and distributing
* the program and assume all risks associated with your exercise
* of rights with respect to the program, including but not limited
* to infringement of third party rights, the risks and costs of
* program errors, damage to or loss of data, programs or equipment,
* and unavailability or interruption of operations. Under no
* circumstances will the contributor of this Program be liable for
* any damages of any kind arising from your use or distribution of
* this program.
*/
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include "ufshcd.h"
#include "ufshcd-pltfrm.h"
#include "unipro.h"
#define UFSHCD_DEFAULT_LANES_PER_DIRECTION 2
static int ufshcd_parse_clock_info(struct ufs_hba *hba)
{
int ret = 0;
int cnt;
int i;
struct device *dev = hba->dev;
struct device_node *np = dev->of_node;
char *name;
u32 *clkfreq = NULL;
struct ufs_clk_info *clki;
int len = 0;
size_t sz = 0;
if (!np)
goto out;
cnt = of_property_count_strings(np, "clock-names");
if (!cnt || (cnt == -EINVAL)) {
dev_info(dev, "%s: Unable to find clocks, assuming enabled\n",
__func__);
} else if (cnt < 0) {
dev_err(dev, "%s: count clock strings failed, err %d\n",
__func__, cnt);
ret = cnt;
}
if (cnt <= 0)
goto out;
if (!of_get_property(np, "freq-table-hz", &len)) {
dev_info(dev, "freq-table-hz property not specified\n");
goto out;
}
if (len <= 0)
goto out;
sz = len / sizeof(*clkfreq);
if (sz != 2 * cnt) {
dev_err(dev, "%s len mismatch\n", "freq-table-hz");
ret = -EINVAL;
goto out;
}
clkfreq = devm_kcalloc(dev, sz, sizeof(*clkfreq),
GFP_KERNEL);
if (!clkfreq) {
ret = -ENOMEM;
goto out;
}
ret = of_property_read_u32_array(np, "freq-table-hz",
clkfreq, sz);
if (ret && (ret != -EINVAL)) {
dev_err(dev, "%s: error reading array %d\n",
"freq-table-hz", ret);
return ret;
}
for (i = 0; i < sz; i += 2) {
ret = of_property_read_string_index(np,
"clock-names", i/2, (const char **)&name);
if (ret)
goto out;
clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL);
if (!clki) {
ret = -ENOMEM;
goto out;
}
clki->min_freq = clkfreq[i];
clki->max_freq = clkfreq[i+1];
clki->name = kstrdup(name, GFP_KERNEL);
dev_dbg(dev, "%s: min %u max %u name %s\n", "freq-table-hz",
clki->min_freq, clki->max_freq, clki->name);
list_add_tail(&clki->list, &hba->clk_list_head);
}
out:
return ret;
}
#define MAX_PROP_SIZE 32
static int ufshcd_populate_vreg(struct device *dev, const char *name,
struct ufs_vreg **out_vreg)
{
int ret = 0;
char prop_name[MAX_PROP_SIZE];
struct ufs_vreg *vreg = NULL;
struct device_node *np = dev->of_node;
if (!np) {
dev_err(dev, "%s: non DT initialization\n", __func__);
goto out;
}
snprintf(prop_name, MAX_PROP_SIZE, "%s-supply", name);
if (!of_parse_phandle(np, prop_name, 0)) {
dev_info(dev, "%s: Unable to find %s regulator, assuming enabled\n",
__func__, prop_name);
goto out;
}
vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
if (!vreg)
return -ENOMEM;
vreg->name = kstrdup(name, GFP_KERNEL);
snprintf(prop_name, MAX_PROP_SIZE, "%s-max-microamp", name);
if (of_property_read_u32(np, prop_name, &vreg->max_uA)) {
dev_info(dev, "%s: unable to find %s\n", __func__, prop_name);
vreg->max_uA = 0;
}
if (!strcmp(name, "vcc")) {
if (of_property_read_bool(np, "vcc-supply-1p8")) {
vreg->min_uV = UFS_VREG_VCC_1P8_MIN_UV;
vreg->max_uV = UFS_VREG_VCC_1P8_MAX_UV;
} else {
vreg->min_uV = UFS_VREG_VCC_MIN_UV;
vreg->max_uV = UFS_VREG_VCC_MAX_UV;
}
} else if (!strcmp(name, "vccq")) {
vreg->min_uV = UFS_VREG_VCCQ_MIN_UV;
vreg->max_uV = UFS_VREG_VCCQ_MAX_UV;
} else if (!strcmp(name, "vccq2")) {
vreg->min_uV = UFS_VREG_VCCQ2_MIN_UV;
vreg->max_uV = UFS_VREG_VCCQ2_MAX_UV;
}
goto out;
out:
if (!ret)
*out_vreg = vreg;
return ret;
}
/**
* ufshcd_parse_regulator_info - get regulator info from device tree
* @hba: per adapter instance
*
* Get regulator info from device tree for vcc, vccq, vccq2 power supplies.
* If any of the supplies are not defined it is assumed that they are always-on
* and hence return zero. If the property is defined but parsing is failed
* then return corresponding error.
*/
static int ufshcd_parse_regulator_info(struct ufs_hba *hba)
{
int err;
struct device *dev = hba->dev;
struct ufs_vreg_info *info = &hba->vreg_info;
err = ufshcd_populate_vreg(dev, "vdd-hba", &info->vdd_hba);
if (err)
goto out;
err = ufshcd_populate_vreg(dev, "vcc", &info->vcc);
if (err)
goto out;
err = ufshcd_populate_vreg(dev, "vccq", &info->vccq);
if (err)
goto out;
err = ufshcd_populate_vreg(dev, "vccq2", &info->vccq2);
out:
return err;
}
#ifdef CONFIG_PM
/**
* ufshcd_pltfrm_suspend - suspend power management function
* @dev: pointer to device handle
*
* Returns 0 if successful
* Returns non-zero otherwise
*/
int ufshcd_pltfrm_suspend(struct device *dev)
{
return ufshcd_system_suspend(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_suspend);
/**
* ufshcd_pltfrm_resume - resume power management function
* @dev: pointer to device handle
*
* Returns 0 if successful
* Returns non-zero otherwise
*/
int ufshcd_pltfrm_resume(struct device *dev)
{
return ufshcd_system_resume(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_resume);
int ufshcd_pltfrm_runtime_suspend(struct device *dev)
{
return ufshcd_runtime_suspend(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_suspend);
int ufshcd_pltfrm_runtime_resume(struct device *dev)
{
return ufshcd_runtime_resume(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_resume);
int ufshcd_pltfrm_runtime_idle(struct device *dev)
{
return ufshcd_runtime_idle(dev_get_drvdata(dev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_idle);
#endif /* CONFIG_PM */
void ufshcd_pltfrm_shutdown(struct platform_device *pdev)
{
ufshcd_shutdown((struct ufs_hba *)platform_get_drvdata(pdev));
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_shutdown);
static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
{
struct device *dev = hba->dev;
int ret;
ret = of_property_read_u32(dev->of_node, "lanes-per-direction",
&hba->lanes_per_direction);
if (ret) {
dev_dbg(hba->dev,
"%s: failed to read lanes-per-direction, ret=%d\n",
__func__, ret);
hba->lanes_per_direction = UFSHCD_DEFAULT_LANES_PER_DIRECTION;
}
}
/**
* ufshcd_get_pwr_dev_param - get finally agreed attributes for
* power mode change
* @pltfrm_param: pointer to platform parameters
* @dev_max: pointer to device attributes
* @agreed_pwr: returned agreed attributes
*
* Returns 0 on success, non-zero value on failure
*/
int ufshcd_get_pwr_dev_param(struct ufs_dev_params *pltfrm_param,
struct ufs_pa_layer_attr *dev_max,
struct ufs_pa_layer_attr *agreed_pwr)
{
int min_pltfrm_gear;
int min_dev_gear;
bool is_dev_sup_hs = false;
bool is_pltfrm_max_hs = false;
if (dev_max->pwr_rx == FAST_MODE)
is_dev_sup_hs = true;
if (pltfrm_param->desired_working_mode == UFS_HS_MODE) {
is_pltfrm_max_hs = true;
min_pltfrm_gear = min_t(u32, pltfrm_param->hs_rx_gear,
pltfrm_param->hs_tx_gear);
} else {
min_pltfrm_gear = min_t(u32, pltfrm_param->pwm_rx_gear,
pltfrm_param->pwm_tx_gear);
}
/*
* device doesn't support HS but
* pltfrm_param->desired_working_mode is HS,
* thus device and pltfrm_param don't agree
*/
if (!is_dev_sup_hs && is_pltfrm_max_hs) {
pr_info("%s: device doesn't support HS\n",
__func__);
return -ENOTSUPP;
} else if (is_dev_sup_hs && is_pltfrm_max_hs) {
/*
* since device supports HS, it supports FAST_MODE.
* since pltfrm_param->desired_working_mode is also HS
* then final decision (FAST/FASTAUTO) is done according
* to pltfrm_params as it is the restricting factor
*/
agreed_pwr->pwr_rx = pltfrm_param->rx_pwr_hs;
agreed_pwr->pwr_tx = agreed_pwr->pwr_rx;
} else {
/*
* here pltfrm_param->desired_working_mode is PWM.
* it doesn't matter whether device supports HS or PWM,
* in both cases pltfrm_param->desired_working_mode will
* determine the mode
*/
agreed_pwr->pwr_rx = pltfrm_param->rx_pwr_pwm;
agreed_pwr->pwr_tx = agreed_pwr->pwr_rx;
}
/*
* we would like tx to work in the minimum number of lanes
* between device capability and vendor preferences.
* the same decision will be made for rx
*/
agreed_pwr->lane_tx = min_t(u32, dev_max->lane_tx,
pltfrm_param->tx_lanes);
agreed_pwr->lane_rx = min_t(u32, dev_max->lane_rx,
pltfrm_param->rx_lanes);
/* device maximum gear is the minimum between device rx and tx gears */
min_dev_gear = min_t(u32, dev_max->gear_rx, dev_max->gear_tx);
/*
* if both device capabilities and vendor pre-defined preferences are
* both HS or both PWM then set the minimum gear to be the chosen
* working gear.
* if one is PWM and one is HS then the one that is PWM get to decide
* what is the gear, as it is the one that also decided previously what
* pwr the device will be configured to.
*/
if ((is_dev_sup_hs && is_pltfrm_max_hs) ||
(!is_dev_sup_hs && !is_pltfrm_max_hs)) {
agreed_pwr->gear_rx =
min_t(u32, min_dev_gear, min_pltfrm_gear);
} else if (!is_dev_sup_hs) {
agreed_pwr->gear_rx = min_dev_gear;
} else {
agreed_pwr->gear_rx = min_pltfrm_gear;
}
agreed_pwr->gear_tx = agreed_pwr->gear_rx;
agreed_pwr->hs_rate = pltfrm_param->hs_rate;
return 0;
}
EXPORT_SYMBOL_GPL(ufshcd_get_pwr_dev_param);
/**
* ufshcd_pltfrm_init - probe routine of the driver
* @pdev: pointer to Platform device handle
* @vops: pointer to variant ops
*
* Returns 0 on success, non-zero value on failure
*/
int ufshcd_pltfrm_init(struct platform_device *pdev,
const struct ufs_hba_variant_ops *vops)
{
struct ufs_hba *hba;
void __iomem *mmio_base;
struct resource *mem_res;
int irq, err;
struct device *dev = &pdev->dev;
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mmio_base = devm_ioremap_resource(dev, mem_res);
if (IS_ERR(mmio_base)) {
err = PTR_ERR(mmio_base);
goto out;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(dev, "IRQ resource not available\n");
err = -ENODEV;
goto out;
}
err = ufshcd_alloc_host(dev, &hba);
if (err) {
dev_err(&pdev->dev, "Allocation failed\n");
goto out;
}
hba->vops = vops;
err = ufshcd_parse_clock_info(hba);
if (err) {
dev_err(&pdev->dev, "%s: clock parse failed %d\n",
__func__, err);
goto dealloc_host;
}
err = ufshcd_parse_regulator_info(hba);
if (err) {
dev_err(&pdev->dev, "%s: regulator init failed %d\n",
__func__, err);
goto dealloc_host;
}
ufshcd_init_lanes_per_dir(hba);
err = ufshcd_init(hba, mmio_base, irq);
if (err) {
dev_err(dev, "Initialization failed\n");
goto dealloc_host;
}
platform_set_drvdata(pdev, hba);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
return 0;
dealloc_host:
ufshcd_dealloc_host(hba);
out:
return err;
}
EXPORT_SYMBOL_GPL(ufshcd_pltfrm_init);
MODULE_AUTHOR("Santosh Yaragnavi <santosh.sy@samsung.com>");
MODULE_AUTHOR("Vinayak Holikatti <h.vinayak@samsung.com>");
MODULE_DESCRIPTION("UFS host controller Platform bus based glue driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(UFSHCD_DRIVER_VERSION);