devfreq requires that the client operates on actual frequencies, not
only 0 and UMAX_INT and as such UFS brok with the introduction of
f1d981eaecf8 ("PM / devfreq: Use the available min/max frequency").

This patch registers the frequencies of the first clock with devfreq and
use these to determine if we're trying to step up or down.

Signed-off-by: Bjorn Andersson <bjorn.anders...@linaro.org>
---
 drivers/scsi/ufs/ufshcd.c | 39 ++++++++++++++++++++++++++++++++-------
 1 file changed, 32 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 2253f24309ec..07b1f3c7bd2d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1168,16 +1168,13 @@ static int ufshcd_devfreq_target(struct device *dev,
        struct ufs_hba *hba = dev_get_drvdata(dev);
        ktime_t start;
        bool scale_up, sched_clk_scaling_suspend_work = false;
+       struct list_head *clk_list = &hba->clk_list_head;
+       struct ufs_clk_info *clki;
        unsigned long irq_flags;
 
        if (!ufshcd_is_clkscaling_supported(hba))
                return -EINVAL;
 
-       if ((*freq > 0) && (*freq < UINT_MAX)) {
-               dev_err(hba->dev, "%s: invalid freq = %lu\n", __func__, *freq);
-               return -EINVAL;
-       }
-
        spin_lock_irqsave(hba->host->host_lock, irq_flags);
        if (ufshcd_eh_in_progress(hba)) {
                spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
@@ -1187,7 +1184,13 @@ static int ufshcd_devfreq_target(struct device *dev,
        if (!hba->clk_scaling.active_reqs)
                sched_clk_scaling_suspend_work = true;
 
-       scale_up = (*freq == UINT_MAX) ? true : false;
+       if (list_empty(clk_list)) {
+               spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
+               goto out;
+       }
+
+       clki = list_first_entry(&hba->clk_list_head, struct ufs_clk_info, list);
+       scale_up = (*freq == clki->max_freq) ? true : false;
        if (!ufshcd_is_devfreq_scaling_required(hba, scale_up)) {
                spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
                ret = 0;
@@ -1257,11 +1260,33 @@ static struct devfreq_dev_profile ufs_devfreq_profile = 
{
 
 static int ufshcd_devfreq_init(struct ufs_hba *hba)
 {
+       struct devfreq_dev_profile *profile;
+       struct list_head *clk_list = &hba->clk_list_head;
+       struct ufs_clk_info *clki;
        struct devfreq *devfreq;
        int ret;
 
+       /* Skip devfreq if we don't have any clocks in the list */
+       if (list_empty(clk_list))
+               return 0;
+
+       profile = devm_kmemdup(hba->dev, &ufs_devfreq_profile,
+                              sizeof(ufs_devfreq_profile), GFP_KERNEL);
+       if (!profile)
+               return -ENOMEM;
+
+       profile->max_state = 2;
+       profile->freq_table = devm_kcalloc(hba->dev, profile->max_state,
+                                          sizeof(unsigned long), GFP_KERNEL);
+       if (!profile->freq_table)
+               return -ENOMEM;
+
+       clki = list_first_entry(&hba->clk_list_head, struct ufs_clk_info, list);
+       profile->freq_table[0] = clki->min_freq;
+       profile->freq_table[1] = clki->max_freq;
+
        devfreq = devm_devfreq_add_device(hba->dev,
-                       &ufs_devfreq_profile,
+                       profile,
                        "simple_ondemand",
                        NULL);
        if (IS_ERR(devfreq)) {
-- 
2.16.2

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