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Merge branch 'i2c/for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Browse Source 
Pull i2c updates from Wolfram Sang:

 - Peter Rosin did some major rework on the locking of i2c muxes by
   seperating parent-locked muxes and mux-locked muxes.

   This avoids deadlocks/workarounds when the mux itself needs i2c
   commands for muxing.  And as a side-effect, other workarounds in the
   media layer could be eliminated.  Also, Peter stepped up as the i2c
   mux maintainer and will keep an eye on these changes.

 - major updates to the octeon driver

 - add a helper to the core to generate the address+rw_bit octal and
   make drivers use it

 - quite a bunch of driver updates

* 'i2c/for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (84 commits)
  i2c: rcar: add DMA support
  i2c: st: Implement bus clear
  i2c: only check scl functions when using generic recovery
  i2c: algo-bit: declare i2c_bit_quirk_no_clk_stretch as static
  i2c: tegra: disable clock before returning error
  [media] rtl2832: regmap is aware of lockdep, drop local locking hack
  [media] rtl2832_sdr: get rid of empty regmap wrappers
  [media] rtl2832: change the i2c gate to be mux-locked
  [media] si2168: change the i2c gate to be mux-locked
  iio: imu: inv_mpu6050: change the i2c gate to be mux-locked
  i2c: mux: document i2c muxes and elaborate on parent-/mux-locked muxes
  i2c: mux: relax locking of the top i2c adapter during mux-locked muxing
  i2c: muxes always lock the parent adapter
  i2c: allow adapter drivers to override the adapter locking
  i2c: uniphier: add "\n" at the end of error log
  i2c: mv64xxx: remove CONFIG_HAVE_CLK conditionals
  i2c: mv64xxx: use clk_{prepare_enable,disable_unprepare}
  i2c: mv64xxx: handle probe deferral for the clock
  i2c: mv64xxx: enable the driver on ARCH_MVEBU
  i2c: octeon: Add workaround for broken irqs on CN3860
  ...
This commit is contained in:
Linus Torvalds
2016-05-19 17:48:12 -07:00
parent feaa7cb5c5 73e8b05283
commit 78975f23cb
67 changed files with 2709 additions and 1506 deletions
Download Patch File Download Diff File Expand all files Collapse all files

87
drivers/i2c/busses/i2c-rk3x.c
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@@ -101,10 +101,7 @@ struct rk3x_i2c {
struct notifier_block clk_rate_nb;
/* Settings */
unsigned int scl_frequency;
unsigned int scl_rise_ns;
unsigned int scl_fall_ns;
unsigned int sda_fall_ns;
struct i2c_timings t;
/* Synchronization & notification */
spinlock_t lock;
@@ -437,10 +434,7 @@ out:
* Calculate divider values for desired SCL frequency
*
* @clk_rate: I2C input clock rate
* @scl_rate: Desired SCL rate
* @scl_rise_ns: How many ns it takes for SCL to rise.
* @scl_fall_ns: How many ns it takes for SCL to fall.
* @sda_fall_ns: How many ns it takes for SDA to fall.
* @t: Known I2C timing information.
* @div_low: Divider output for low
* @div_high: Divider output for high
*
@@ -448,11 +442,10 @@ out:
* a best-effort divider value is returned in divs. If the target rate is
* too high, we silently use the highest possible rate.
*/
static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
unsigned long scl_rise_ns,
unsigned long scl_fall_ns,
unsigned long sda_fall_ns,
unsigned long *div_low, unsigned long *div_high)
static int rk3x_i2c_calc_divs(unsigned long clk_rate,
struct i2c_timings *t,
unsigned long *div_low,
unsigned long *div_high)
{
unsigned long spec_min_low_ns, spec_min_high_ns;
unsigned long spec_setup_start, spec_max_data_hold_ns;
@@ -472,12 +465,12 @@ static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
int ret = 0;
/* Only support standard-mode and fast-mode */
if (WARN_ON(scl_rate > 400000))
scl_rate = 400000;
if (WARN_ON(t->bus_freq_hz > 400000))
t->bus_freq_hz = 400000;
/* prevent scl_rate_khz from becoming 0 */
if (WARN_ON(scl_rate < 1000))
scl_rate = 1000;
if (WARN_ON(t->bus_freq_hz < 1000))
t->bus_freq_hz = 1000;
/*
* min_low_ns: The minimum number of ns we need to hold low to
@@ -491,7 +484,7 @@ static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
* This is because the i2c host on Rockchip holds the data line
* for half the low time.
*/
if (scl_rate <= 100000) {
if (t->bus_freq_hz <= 100000) {
/* Standard-mode */
spec_min_low_ns = 4700;
spec_setup_start = 4700;
@@ -506,7 +499,7 @@ static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
spec_max_data_hold_ns = 900;
data_hold_buffer_ns = 50;
}
min_high_ns = scl_rise_ns + spec_min_high_ns;
min_high_ns = t->scl_rise_ns + spec_min_high_ns;
/*
* Timings for repeated start:
@@ -517,18 +510,18 @@ static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
* we meet tSU;STA and tHD;STA times.
*/
min_high_ns = max(min_high_ns,
DIV_ROUND_UP((scl_rise_ns + spec_setup_start) * 1000, 875));
DIV_ROUND_UP((t->scl_rise_ns + spec_setup_start) * 1000, 875));
min_high_ns = max(min_high_ns,
DIV_ROUND_UP((scl_rise_ns + spec_setup_start +
sda_fall_ns + spec_min_high_ns), 2));
DIV_ROUND_UP((t->scl_rise_ns + spec_setup_start +
t->sda_fall_ns + spec_min_high_ns), 2));
min_low_ns = scl_fall_ns + spec_min_low_ns;
min_low_ns = t->scl_fall_ns + spec_min_low_ns;
max_low_ns = spec_max_data_hold_ns * 2 - data_hold_buffer_ns;
min_total_ns = min_low_ns + min_high_ns;
/* Adjust to avoid overflow */
clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000);
scl_rate_khz = scl_rate / 1000;
scl_rate_khz = t->bus_freq_hz / 1000;
/*
* We need the total div to be >= this number
@@ -616,14 +609,13 @@ static int rk3x_i2c_calc_divs(unsigned long clk_rate, unsigned long scl_rate,
static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate)
{
struct i2c_timings *t = &i2c->t;
unsigned long div_low, div_high;
u64 t_low_ns, t_high_ns;
int ret;
ret = rk3x_i2c_calc_divs(clk_rate, i2c->scl_frequency, i2c->scl_rise_ns,
i2c->scl_fall_ns, i2c->sda_fall_ns,
&div_low, &div_high);
WARN_ONCE(ret != 0, "Could not reach SCL freq %u", i2c->scl_frequency);
ret = rk3x_i2c_calc_divs(clk_rate, t, &div_low, &div_high);
WARN_ONCE(ret != 0, "Could not reach SCL freq %u", t->bus_freq_hz);
clk_enable(i2c->clk);
i2c_writel(i2c, (div_high << 16) | (div_low & 0xffff), REG_CLKDIV);
@@ -634,7 +626,7 @@ static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate)
dev_dbg(i2c->dev,
"CLK %lukhz, Req %uns, Act low %lluns high %lluns\n",
clk_rate / 1000,
1000000000 / i2c->scl_frequency,
1000000000 / t->bus_freq_hz,
t_low_ns, t_high_ns);
}
@@ -664,9 +656,7 @@ static int rk3x_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long
switch (event) {
case PRE_RATE_CHANGE:
if (rk3x_i2c_calc_divs(ndata->new_rate, i2c->scl_frequency,
i2c->scl_rise_ns, i2c->scl_fall_ns,
i2c->sda_fall_ns,
if (rk3x_i2c_calc_divs(ndata->new_rate, &i2c->t,
&div_low, &div_high) != 0)
return NOTIFY_STOP;
@@ -880,37 +870,8 @@ static int rk3x_i2c_probe(struct platform_device *pdev)
match = of_match_node(rk3x_i2c_match, np);
i2c->soc_data = (struct rk3x_i2c_soc_data *)match->data;
if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
&i2c->scl_frequency)) {
dev_info(&pdev->dev, "using default SCL frequency: %d\n",
DEFAULT_SCL_RATE);
i2c->scl_frequency = DEFAULT_SCL_RATE;
}
if (i2c->scl_frequency == 0 || i2c->scl_frequency > 400 * 1000) {
dev_warn(&pdev->dev, "invalid SCL frequency specified.\n");
dev_warn(&pdev->dev, "using default SCL frequency: %d\n",
DEFAULT_SCL_RATE);
i2c->scl_frequency = DEFAULT_SCL_RATE;
}
/*
* Read rise and fall time from device tree. If not available use
* the default maximum timing from the specification.
*/
if (of_property_read_u32(pdev->dev.of_node, "i2c-scl-rising-time-ns",
&i2c->scl_rise_ns)) {
if (i2c->scl_frequency <= 100000)
i2c->scl_rise_ns = 1000;
else
i2c->scl_rise_ns = 300;
}
if (of_property_read_u32(pdev->dev.of_node, "i2c-scl-falling-time-ns",
&i2c->scl_fall_ns))
i2c->scl_fall_ns = 300;
if (of_property_read_u32(pdev->dev.of_node, "i2c-sda-falling-time-ns",
&i2c->sda_fall_ns))
i2c->sda_fall_ns = i2c->scl_fall_ns;
/* use common interface to get I2C timing properties */
i2c_parse_fw_timings(&pdev->dev, &i2c->t, true);
strlcpy(i2c->adap.name, "rk3x-i2c", sizeof(i2c->adap.name));
i2c->adap.owner = THIS_MODULE;