From: Jan Glauber <jglauber@cavium.com>
To: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
David Daney <ddaney@caviumnetworks.com>,
Jan Glauber <jglauber@cavium.com>
Subject: [PATCH v6 02/19] i2c: octeon: Move set-clock and init-lowlevel upward
Date: Mon, 11 Apr 2016 17:28:33 +0200 [thread overview]
Message-ID: <0c8bf145fbe732f19bf6b44291d06b66cc3fb1cb.1460387640.git.jglauber@cavium.com> (raw)
In-Reply-To: <cover.1460387640.git.jglauber@cavium.com>
In-Reply-To: <cover.1460387640.git.jglauber@cavium.com>
No functional change, just moving the functions upward in
preparation of improving the recovery.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
---
drivers/i2c/busses/i2c-octeon.c | 126 ++++++++++++++++++++--------------------
1 file changed, 63 insertions(+), 63 deletions(-)
diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index c4abf16..f647667 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -214,6 +214,69 @@ static int octeon_i2c_wait(struct octeon_i2c *i2c)
return 0;
}
+/* calculate and set clock divisors */
+static 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;
+
+ for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
+ /*
+ * An mdiv value of less than 2 seems to not work well
+ * with ds1337 RTCs, so we constrain it to larger values.
+ */
+ for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
+ /*
+ * For given ndiv and mdiv values check the
+ * two closest thp values.
+ */
+ tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
+ tclk *= (1 << ndiv_idx);
+ 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));
+ foscl = foscl / (1 << ndiv_idx);
+ foscl = foscl / (mdiv_idx + 1) / 10;
+ diff = abs(foscl - i2c->twsi_freq);
+ if (diff < delta_hz) {
+ delta_hz = diff;
+ thp = thp_idx;
+ mdiv = mdiv_idx;
+ ndiv = ndiv_idx;
+ }
+ }
+ }
+ }
+ octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
+{
+ u8 status;
+ int tries;
+
+ /* disable high level controller, enable bus access */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ /* reset controller */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+ for (tries = 10; tries; tries--) {
+ udelay(1);
+ status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ if (status == STAT_IDLE)
+ return 0;
+ }
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
+ return -EIO;
+}
+
/**
* octeon_i2c_start - send START to the bus
* @i2c: The struct octeon_i2c
@@ -428,69 +491,6 @@ static struct i2c_adapter octeon_i2c_ops = {
.algo = &octeon_i2c_algo,
};
-/* calculate and set clock divisors */
-static 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;
-
- for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
- /*
- * An mdiv value of less than 2 seems to not work well
- * with ds1337 RTCs, so we constrain it to larger values.
- */
- for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
- /*
- * For given ndiv and mdiv values check the
- * two closest thp values.
- */
- tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
- tclk *= (1 << ndiv_idx);
- 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));
- foscl = foscl / (1 << ndiv_idx);
- foscl = foscl / (mdiv_idx + 1) / 10;
- diff = abs(foscl - i2c->twsi_freq);
- if (diff < delta_hz) {
- delta_hz = diff;
- thp = thp_idx;
- mdiv = mdiv_idx;
- ndiv = ndiv_idx;
- }
- }
- }
- }
- octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
-}
-
-static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
-{
- u8 status;
- int tries;
-
- /* disable high level controller, enable bus access */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- /* reset controller */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
-
- for (tries = 10; tries; tries--) {
- udelay(1);
- status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- if (status == STAT_IDLE)
- return 0;
- }
- dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
- return -EIO;
-}
-
static int octeon_i2c_probe(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
--
1.9.1
next prev parent reply other threads:[~2016-04-11 15:38 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-11 15:28 [PATCH v6 00/19] i2c-octeon and i2c-thunderx drivers Jan Glauber
2016-04-11 15:28 ` [PATCH v6 01/19] i2c: octeon: Increase retry default and use fixed timeout value Jan Glauber
2016-04-13 8:39 ` Wolfram Sang
2016-04-11 15:28 ` Jan Glauber [this message]
2016-04-13 8:39 ` [PATCH v6 02/19] i2c: octeon: Move set-clock and init-lowlevel upward Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 03/19] i2c: octeon: Rename [read|write]_sw to reg_[read|write] Jan Glauber
2016-04-13 8:44 ` Wolfram Sang
2016-04-14 7:58 ` Jan Glauber
2016-04-14 8:58 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 04/19] i2c: octeon: Introduce helper functions for register access Jan Glauber
2016-04-13 8:45 ` Wolfram Sang
2016-04-14 8:05 ` Jan Glauber
2016-04-14 8:58 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 05/19] i2c: octeon: Remove superfluous check in octeon_i2c_test_iflg Jan Glauber
2016-04-14 8:59 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 06/19] i2c: octeon: Improve error status checking Jan Glauber
2016-04-13 8:55 ` Wolfram Sang
2016-04-14 8:10 ` Jan Glauber
2016-04-14 9:01 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 07/19] i2c: octeon: Use i2c recovery framework Jan Glauber
2016-04-20 21:31 ` Wolfram Sang
2016-04-21 13:08 ` Jan Glauber
2016-04-21 13:54 ` Wolfram Sang
2016-04-21 17:51 ` Jan Glauber
2016-04-21 21:33 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 08/19] i2c: octeon: Enable High-Level Controller Jan Glauber
2016-04-20 21:43 ` Wolfram Sang
2016-04-20 21:55 ` David Daney
2016-04-21 13:40 ` Jan Glauber
2016-04-21 13:55 ` Wolfram Sang
2016-04-21 14:10 ` Jan Glauber
2016-04-11 15:28 ` [PATCH v6 09/19] dt-bindings: i2c: Add Octeon cn78xx TWSI Jan Glauber
2016-04-11 15:28 ` [PATCH v6 10/19] i2c: octeon: Add support for cn78xx chips Jan Glauber
2016-04-20 21:52 ` Wolfram Sang
2016-04-20 22:28 ` David Daney
2016-04-25 21:45 ` Wolfram Sang
2016-04-11 15:28 ` [PATCH v6 11/19] i2c: octeon: Flush TWSI writes with readback Jan Glauber
2016-04-11 15:28 ` [PATCH v6 12/19] i2c: octeon: Faster operation when IFLG signals late Jan Glauber
2016-04-11 15:28 ` [PATCH v6 13/19] i2c: octeon: Add workaround for broken irqs on CN3860 Jan Glauber
2016-04-11 15:28 ` [PATCH v6 14/19] i2c: octeon: Move read function before write Jan Glauber
2016-04-11 15:28 ` [PATCH v6 15/19] i2c: octeon: Rename driver to prepare for split Jan Glauber
2016-04-11 15:28 ` [PATCH v6 16/19] i2c: octeon: Split the driver into two parts Jan Glauber
2016-04-11 15:28 ` [PATCH v6 17/19] i2c: thunderx: Add i2c driver for ThunderX SOC Jan Glauber
2016-04-11 15:28 ` [PATCH v6 18/19] i2c: octeon,thunderx: Move register offsets to struct Jan Glauber
2016-04-11 15:28 ` [PATCH v6 19/19] i2c: thunderx: Add smbus alert support Jan Glauber
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