staging: wilc1000: give usleep_range a range
authorNicholas Mc Guire <hofrat@osadl.org>
Thu, 11 Apr 2019 03:31:21 +0000 (05:31 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 16 Apr 2019 11:15:54 +0000 (13:15 +0200)
usleep_range() is called in non-atomic context so there is little point
in setting min==max as the jitter of hrtimer is determined by interruptions
anyway. usleep_range can only perform the intended coalescence if some
room for placing the hrtimer is provided. Given the range of milliseconds
the delay will be 2+ anyway - so make it 2-2.5 ms which gives hrtimers
space to optimize without negatively impacting performance.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/wilc1000/wilc_wlan.c

index f5443de..2b309c8 100644 (file)
@@ -408,7 +408,7 @@ void chip_wakeup(struct wilc *wilc)
                        wilc->hif_func->hif_write_reg(wilc, 1, reg & ~BIT(1));
 
                        do {
-                               usleep_range(2 * 1000, 2 * 1000);
+                               usleep_range(2000, 2500);
                                wilc_get_chipid(wilc, true);
                        } while (wilc_get_chipid(wilc, true) == 0);
                } while (wilc_get_chipid(wilc, true) == 0);
@@ -423,7 +423,7 @@ void chip_wakeup(struct wilc *wilc)
                                                     &clk_status_reg);
 
                        while ((clk_status_reg & 0x1) == 0) {
-                               usleep_range(2 * 1000, 2 * 1000);
+                               usleep_range(2000, 2500);
 
                                wilc->hif_func->hif_read_reg(wilc, 0xf1,
                                                             &clk_status_reg);