On 3/6/20 11:09 AM, Patrick Delaunay wrote: > From: Alain Volmat <[email protected]> > > Do not limit to 3 (100KHz, 400KHz, 1MHz) bus frequencies, but > instead allow for any frequency. Depending on the requested > frequency (via the clock-frequency DT entry), use the spec > data from either Standard, Fast or Fast Plus mode. > > In order to do so, the driver do not use anymore spec identifier > by directly handle the requested frequency and from it retrieve > the corresponding spec data to be used for the computation > of the timing register. > > Signed-off-by: Alain Volmat <[email protected]> > Reviewed-by: Patrick DELAUNAY <[email protected]> > Signed-off-by: Patrick Delaunay <[email protected]> > --- > > drivers/i2c/stm32f7_i2c.c | 105 +++++++++++++++++++++----------------- > 1 file changed, 59 insertions(+), 46 deletions(-) > > diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c > index 7d046c1a1e..fc5c1221e1 100644 > --- a/drivers/i2c/stm32f7_i2c.c > +++ b/drivers/i2c/stm32f7_i2c.c > @@ -7,10 +7,10 @@ > #include <clk.h> > #include <dm.h> > #include <i2c.h> > -#include <malloc.h> > #include <reset.h> > > #include <dm/device.h> > +#include <linux/err.h> > #include <linux/io.h> > > /* STM32 I2C registers */ > @@ -145,7 +145,6 @@ struct stm32_i2c_spec { > > /** > * struct stm32_i2c_setup - private I2C timing setup parameters > - * @speed: I2C speed mode (standard, Fast Plus) > * @speed_freq: I2C speed frequency (Hz) > * @clock_src: I2C clock source frequency (Hz) > * @rise_time: Rise time (ns) > @@ -154,7 +153,6 @@ struct stm32_i2c_spec { > * @analog_filter: Analog filter delay (On/Off) > */ > struct stm32_i2c_setup { > - enum i2c_speed_mode speed; > u32 speed_freq; > u32 clock_src; > u32 rise_time; > @@ -184,10 +182,11 @@ struct stm32_i2c_priv { > struct stm32_i2c_regs *regs; > struct clk clk; > struct stm32_i2c_setup *setup; > - int speed; > + u32 speed; > }; > > static const struct stm32_i2c_spec i2c_specs[] = { > + /* Standard speed - 100 KHz */ > [IC_SPEED_MODE_STANDARD] = { > .rate = I2C_SPEED_STANDARD_RATE, > .rate_min = 8000, > @@ -200,6 +199,7 @@ static const struct stm32_i2c_spec i2c_specs[] = { > .l_min = 4700, > .h_min = 4000, > }, > + /* Fast speed - 400 KHz */ > [IC_SPEED_MODE_FAST] = { > .rate = I2C_SPEED_FAST_RATE, > .rate_min = 320000, > @@ -212,6 +212,7 @@ static const struct stm32_i2c_spec i2c_specs[] = { > .l_min = 1300, > .h_min = 600, > }, > + /* Fast Plus Speed - 1 MHz */ > [IC_SPEED_MODE_FAST_PLUS] = { > .rate = I2C_SPEED_FAST_PLUS_RATE, > .rate_min = 800000, > @@ -474,6 +475,7 @@ static int stm32_i2c_xfer(struct udevice *bus, struct > i2c_msg *msg, > } > > static int stm32_i2c_compute_solutions(struct stm32_i2c_setup *setup, > + const struct stm32_i2c_spec *specs, > struct list_head *solutions) > { > struct stm32_i2c_timings *v; > @@ -490,13 +492,13 @@ static int stm32_i2c_compute_solutions(struct > stm32_i2c_setup *setup, > af_delay_max = setup->analog_filter ? > STM32_I2C_ANALOG_FILTER_DELAY_MAX : 0; > > - sdadel_min = i2c_specs[setup->speed].hddat_min + setup->fall_time - > + sdadel_min = specs->hddat_min + setup->fall_time - > af_delay_min - (setup->dnf + 3) * i2cclk; > > - sdadel_max = i2c_specs[setup->speed].vddat_max - setup->rise_time - > + sdadel_max = specs->vddat_max - setup->rise_time - > af_delay_max - (setup->dnf + 4) * i2cclk; > > - scldel_min = setup->rise_time + i2c_specs[setup->speed].sudat_min; > + scldel_min = setup->rise_time + specs->sudat_min; > > if (sdadel_min < 0) > sdadel_min = 0; > @@ -548,6 +550,7 @@ static int stm32_i2c_compute_solutions(struct > stm32_i2c_setup *setup, > } > > static int stm32_i2c_choose_solution(struct stm32_i2c_setup *setup, > + const struct stm32_i2c_spec *specs, > struct list_head *solutions, > struct stm32_i2c_timings *s) > { > @@ -570,8 +573,8 @@ static int stm32_i2c_choose_solution(struct > stm32_i2c_setup *setup, > dnf_delay = setup->dnf * i2cclk; > > tsync = af_delay_min + dnf_delay + (2 * i2cclk); > - clk_max = STM32_NSEC_PER_SEC / i2c_specs[setup->speed].rate_min; > - clk_min = STM32_NSEC_PER_SEC / i2c_specs[setup->speed].rate_max; > + clk_max = STM32_NSEC_PER_SEC / specs->rate_min; > + clk_min = STM32_NSEC_PER_SEC / specs->rate_max; > > /* > * Among Prescaler possibilities discovered above figures out SCL Low > @@ -589,7 +592,7 @@ static int stm32_i2c_choose_solution(struct > stm32_i2c_setup *setup, > for (l = 0; l < STM32_SCLL_MAX; l++) { > u32 tscl_l = (l + 1) * prescaler + tsync; > > - if ((tscl_l < i2c_specs[setup->speed].l_min) || > + if (tscl_l < specs->l_min || > (i2cclk >= > ((tscl_l - af_delay_min - dnf_delay) / 4))) { > continue; > @@ -601,7 +604,7 @@ static int stm32_i2c_choose_solution(struct > stm32_i2c_setup *setup, > setup->rise_time + setup->fall_time; > > if ((tscl >= clk_min) && (tscl <= clk_max) && > - (tscl_h >= i2c_specs[setup->speed].h_min) && > + (tscl_h >= specs->h_min) && > (i2cclk < tscl_h)) { > u32 clk_error; > > @@ -630,26 +633,40 @@ static int stm32_i2c_choose_solution(struct > stm32_i2c_setup *setup, > return ret; > } > > +static const struct stm32_i2c_spec *get_specs(u32 rate) > +{ > + unsigned int i; > + > + for (i = 0; i < ARRAY_SIZE(i2c_specs); i++) > + if (rate <= i2c_specs[i].rate) > + return &i2c_specs[i]; > + > + /* NOT REACHED */ > + return ERR_PTR(-EINVAL); > +} > + > static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv, > struct stm32_i2c_setup *setup, > struct stm32_i2c_timings *output) > { > + const struct stm32_i2c_spec *specs; > struct stm32_i2c_timings *v, *_v; > struct list_head solutions; > int ret; > > - if (setup->speed >= ARRAY_SIZE(i2c_specs)) { > - pr_err("%s: speed out of bound {%d/%d}\n", __func__, > - setup->speed, ARRAY_SIZE(i2c_specs) - 1); > + specs = get_specs(setup->speed_freq); > + if (specs == ERR_PTR(-EINVAL)) { > + pr_err("%s: speed out of bound {%d}\n", __func__, > + setup->speed_freq); > return -EINVAL; > } > > - if ((setup->rise_time > i2c_specs[setup->speed].rise_max) || > - (setup->fall_time > i2c_specs[setup->speed].fall_max)) { > + if (setup->rise_time > specs->rise_max || > + setup->fall_time > specs->fall_max) { > pr_err("%s :timings out of bound Rise{%d>%d}/Fall{%d>%d}\n", > __func__, > - setup->rise_time, i2c_specs[setup->speed].rise_max, > - setup->fall_time, i2c_specs[setup->speed].fall_max); > + setup->rise_time, specs->rise_max, > + setup->fall_time, specs->fall_max); > return -EINVAL; > } > > @@ -659,18 +676,12 @@ static int stm32_i2c_compute_timing(struct > stm32_i2c_priv *i2c_priv, > return -EINVAL; > } > > - if (setup->speed_freq > i2c_specs[setup->speed].rate) { > - pr_err("%s: Freq {%d/%d}\n", __func__, > - setup->speed_freq, i2c_specs[setup->speed].rate); > - return -EINVAL; > - } > - > INIT_LIST_HEAD(&solutions); > - ret = stm32_i2c_compute_solutions(setup, &solutions); > + ret = stm32_i2c_compute_solutions(setup, specs, &solutions); > if (ret) > goto exit; > > - ret = stm32_i2c_choose_solution(setup, &solutions, output); > + ret = stm32_i2c_choose_solution(setup, specs, &solutions, output); > if (ret) > goto exit; > > @@ -689,14 +700,24 @@ exit: > return ret; > } > > +static u32 get_lower_rate(u32 rate) > +{ > + int i; > + > + for (i = ARRAY_SIZE(i2c_specs) - 1; i >= 0; i--) > + if (rate > i2c_specs[i].rate) > + return i2c_specs[i].rate; > + > + return i2c_specs[0].rate; > +} > + > static int stm32_i2c_setup_timing(struct stm32_i2c_priv *i2c_priv, > struct stm32_i2c_timings *timing) > { > struct stm32_i2c_setup *setup = i2c_priv->setup; > int ret = 0; > > - setup->speed = i2c_priv->speed; > - setup->speed_freq = i2c_specs[setup->speed].rate; > + setup->speed_freq = i2c_priv->speed; > setup->clock_src = clk_get_rate(&i2c_priv->clk); > > if (!setup->clock_src) { > @@ -709,13 +730,11 @@ static int stm32_i2c_setup_timing(struct stm32_i2c_priv > *i2c_priv, > if (ret) { > debug("%s: failed to compute I2C timings.\n", > __func__); > - if (i2c_priv->speed > IC_SPEED_MODE_STANDARD) { > - i2c_priv->speed--; > - setup->speed = i2c_priv->speed; > + if (setup->speed_freq > I2C_SPEED_STANDARD_RATE) { > setup->speed_freq = > - i2c_specs[setup->speed].rate; > + get_lower_rate(setup->speed_freq); > debug("%s: downgrade I2C Speed Freq to (%i)\n", > - __func__, i2c_specs[setup->speed].rate); > + __func__, setup->speed_freq); > } else { > break; > } > @@ -727,13 +746,15 @@ static int stm32_i2c_setup_timing(struct stm32_i2c_priv > *i2c_priv, > return ret; > } > > - debug("%s: I2C Speed(%i), Freq(%i), Clk Source(%i)\n", __func__, > - setup->speed, setup->speed_freq, setup->clock_src); > + debug("%s: I2C Freq(%i), Clk Source(%i)\n", __func__, > + setup->speed_freq, setup->clock_src); > debug("%s: I2C Rise(%i) and Fall(%i) Time\n", __func__, > setup->rise_time, setup->fall_time); > debug("%s: I2C Analog Filter(%s), DNF(%i)\n", __func__, > setup->analog_filter ? "On" : "Off", setup->dnf); > > + i2c_priv->speed = setup->speed_freq; > + > return 0; > } > > @@ -773,21 +794,13 @@ static int stm32_i2c_set_bus_speed(struct udevice *bus, > unsigned int speed) > { > struct stm32_i2c_priv *i2c_priv = dev_get_priv(bus); > > - switch (speed) { > - case I2C_SPEED_STANDARD_RATE: > - i2c_priv->speed = IC_SPEED_MODE_STANDARD; > - break; > - case I2C_SPEED_FAST_RATE: > - i2c_priv->speed = IC_SPEED_MODE_FAST; > - break; > - case I2C_SPEED_FAST_PLUS_RATE: > - i2c_priv->speed = IC_SPEED_MODE_FAST_PLUS; > - break; > - default: > + if (speed > I2C_SPEED_FAST_PLUS_RATE) { > debug("%s: Speed %d not supported\n", __func__, speed); > return -EINVAL; > } > > + i2c_priv->speed = speed; > + > return stm32_i2c_hw_config(i2c_priv); > } >
Acked-by: Patrice Chotard <[email protected]> Thanks Patrice
