Hello Stefan,
Am 29.06.2020 um 19:46 schrieb Stefan Bosch:
Changes in relation to FriendlyARM's U-Boot nanopi2-v2016.01:
- i2c/nx_i2c.c: Some adaptions mainly because of changes in "struct udevice".
- several Bugfixes in nx_i2c.c.
- the driver has been for s5p6818 only. Code extended appropriately in order s5p4418 is also working.
- "probe_chip" added.
- pinctrl-driver/dt is used instead of configuring the i2c I/O-pins in the i2c-driver.
- '#ifdef CONFIG...' changed to 'if (IS_ENABLED(CONFIG...))' where possible (and similar).
- livetree API (dev_read_...) is used instead of fdt one (fdt...).
Signed-off-by: Stefan Bosch stefan_b@posteo.net
Reviewed-by: Heiko Schocher hs@denx.de
Nitpick only ...
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diff --git a/drivers/i2c/nx_i2c.c b/drivers/i2c/nx_i2c.c new file mode 100644 index 0000000..cefc774 --- /dev/null +++ b/drivers/i2c/nx_i2c.c @@ -0,0 +1,624 @@
[...]
+static uint i2c_set_clk(struct nx_i2c_bus *bus, uint enb) +{
- struct clk *clk;
- char name[50];
- sprintf(name, "%s.%d", DEV_NAME_I2C, bus->bus_num);
- clk = clk_get((const char *)name);
- if (!clk) {
debug("%s(): clk_get(%s) error!\n",__func__, (const char *)name);return -EINVAL;- }
- if (enb) {
clk_disable(clk);clk_enable(clk);- } else {
clk_disable(clk);- }
You can do here:
clk_disable(clk); if (enb) clk_enable(clk);
- return 0;
+}
+#ifdef CONFIG_ARCH_S5P6818 +/* Set SDA line delay, not available at S5P4418 */ +static int nx_i2c_set_sda_delay(struct nx_i2c_bus *bus) +{
- struct nx_i2c_regs *i2c = bus->regs;
- uint pclk = 0;
- uint t_pclk = 0;
- uint delay = 0;
- /* get input clock of the I2C-controller */
- pclk = i2c_get_clkrate(bus);
- if (bus->sda_delay) {
/* t_pclk = period time of one pclk [ns] */t_pclk = DIV_ROUND_UP(1000, pclk / 1000000);/* delay = number of pclks required for sda_delay [ns] */delay = DIV_ROUND_UP(bus->sda_delay, t_pclk);/* delay = register value (step of 5 clocks) */delay = DIV_ROUND_UP(delay, 5);/* max. possible register value = 3 */if (delay > 3) {
May you use defines here?
delay = 3;debug("%s(): sda-delay des.: %dns, sat. to max.: %dns (granularity: %dns)\n",__func__, bus->sda_delay, t_pclk * delay * 5,t_pclk * 5);} else {debug("%s(): sda-delay des.: %dns, act.: %dns (granularity: %dns)\n",__func__, bus->sda_delay, t_pclk * delay * 5,t_pclk * 5);}delay |= I2CLC_FILTER;- } else {
delay = 0;debug("%s(): sda-delay = 0\n", __func__);- }
- delay &= 0x7;
- writel(delay, &i2c->iiclc);
- return 0;
+} +#endif
+static int nx_i2c_set_bus_speed(struct udevice *dev, uint speed) +{
- struct nx_i2c_bus *bus = dev_get_priv(dev);
- struct nx_i2c_regs *i2c = bus->regs;
- unsigned long pclk, pres = 16, div;
- if (i2c_set_clk(bus, 1))
return -EINVAL;- /* get input clock of the I2C-controller */
- pclk = i2c_get_clkrate(bus);
- /* calculate prescaler and divisor values */
- if ((pclk / pres / (16 + 1)) > speed)
/* set prescaler to 256 */pres = 256;- div = 0;
- /* actual divider = div + 1 */
- while ((pclk / pres / (div + 1)) > speed)
div++;- if (div > 0xF) {
debug("%s(): pres==%ld, div==0x%lx is saturated to 0xF !)\n",__func__, pres, div);div = 0xF;- } else {
debug("%s(): pres==%ld, div==0x%lx)\n", __func__, pres, div);- }
- /* set prescaler, divisor according to pclk, also set ACKGEN, IRQ */
- writel((div & 0x0F) | ((pres == 256) ? 0x40 : 0), &i2c->iiccon);
Ok, I am really nitpicking now ... can you use defines here instead this magic values?
[...]
Thanks!
bye, Heiko