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Diffstat (limited to 'drivers/i2c/busses/i2c-octeon-core.c')
-rw-r--r--drivers/i2c/busses/i2c-octeon-core.c24
1 files changed, 21 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
index d9607905dc2f..75e3779bb650 100644
--- a/drivers/i2c/busses/i2c-octeon-core.c
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -17,6 +17,7 @@
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/pci.h>
#include "i2c-octeon-core.h"
@@ -658,7 +659,16 @@ out:
void octeon_i2c_set_clock(struct octeon_i2c *i2c)
{
int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
- int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+ /* starting value on search for lowest diff */
+ const int huge_delta = 1000000;
+ /*
+ * Find divisors to produce target frequency, start with large delta
+ * to cover wider range of divisors, note thp = TCLK half period.
+ */
+ int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = huge_delta;
+
+ if (octeon_i2c_is_otx2(to_pci_dev(i2c->dev)))
+ thp = 0x3;
for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
/*
@@ -672,17 +682,25 @@ void octeon_i2c_set_clock(struct octeon_i2c *i2c)
*/
tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
tclk *= (1 << ndiv_idx);
- thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+ if (octeon_i2c_is_otx2(to_pci_dev(i2c->dev)))
+ thp_base = (i2c->sys_freq / tclk) - 2;
+ else
+ thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
for (inc = 0; inc <= 1; inc++) {
thp_idx = thp_base + inc;
if (thp_idx < 5 || thp_idx > 0xff)
continue;
- foscl = i2c->sys_freq / (2 * (thp_idx + 1));
+ if (octeon_i2c_is_otx2(to_pci_dev(i2c->dev)))
+ foscl = i2c->sys_freq / (thp_idx + 2);
+ else
+ foscl = i2c->sys_freq /
+ (2 * (thp_idx + 1));
foscl = foscl / (1 << ndiv_idx);
foscl = foscl / (mdiv_idx + 1) / 10;
diff = abs(foscl - i2c->twsi_freq);
+ /* Use it if smaller diff from target */
if (diff < delta_hz) {
delta_hz = diff;
thp = thp_idx;