Dr. H. Nikolaus Schaller wrote: > > Am 03.05.2010 um 22:18 schrieb Graham Gower: > >> On 4 May 2010 05:18, Dr. H. Nikolaus Schaller <h...@computer.org> wrote: >>> >>> Am 03.05.2010 um 21:35 schrieb Dr. H. Nikolaus Schaller: >>> >>> So what can we learn? I think I should look into the sources of the >>> old RTC >>> driver to find out what it is doing differently (with respect to >>> initialization, e.g. GPIO assignment?). >>> >>> Learings: >>> 1. the working driver is at driver/character/rtc_pcf8563.c >> >> drivers/char/rtc_pcf8563.c has been hacked to support Ingenic's i2c code. >> >> >>> 2. it directly calls i2c_open(), i2c_read(), i2c_close() etc. from >>> arch/mips/jz4730/i2c.c >> >> Yes. This i2c driver does not register itself to the kernel as an i2c >> bus driver. It is a total hack. > > And that is enough reason to get rid of it... > >> >> >>> 3. is initialized (pcf_rtc_init) many dmesg lines after hctosys fails >>> (rtc_init) >>> 4. no specific GPIO assignments found >>> 5. i2c_open calls __i2c_enable >>> 6. this is defined in kernel/include/asm/mach-jz4730/ops.h and sets some >>> registers - maybe, this is missing for the "new" i2c driver (at least I >>> haven't seen it in the code I copied from the Qi-Hardware project). > > I had just not seen this call. And I found that the "new" driver also > uses all the __i2c_something() calls. > > What I have now additionally cross-ported from the Qi-JZ4740 kernel is > the platform initialization of the i2c subsystem in > arch/mips/jz4730/platform.c. > > And voila: i2c-tools now find a bus! But I am not sure if it works since > i2cdetect reports all addresses... > > And the "new" RTC driver still does not initialize. > > BR, > Nikolaus
Ingenic's i2c driver from here almost works: http://projects.qi-hardware.com/index.php/p/ingenic-linux-02os-linux-2-6-31-3/source/tree/HEAD/trunk/drivers/i2c/busses I had to apply the following change to fix it for the pcf8563... --- /home/grg/rcs/ingenic-linux-02os-linux-2-6-31-3/drivers/i2c/busses/i2c-jz47xx.c 2010-01-20 12:08:11.000000000 +1030 +++ i2c-jz47xx.c 2010-02-08 11:00:37.000000000 +1030 @@ -30,6 +30,8 @@ #include <asm/jzsoc.h> #include "i2c-jz47xx.h" +#define EEPROM_DEVICE_NUMBER 0x50 /*eeprom device number.20091027*/ + /* I2C protocol */ #define I2C_READ 1 #define I2C_WRITE 0 @@ -107,11 +109,13 @@ int cnt = length; int timeout = 5; +#if 0 /*eeprom device address transfer*/ if(EEPROM_DEVICE_NUMBER == (device & 0xf0)){ device = device | ((sub_addr & 0x0700) >> 8); sub_addr = sub_addr & 0xff; } +#endif L_try_again: @@ -178,11 +182,13 @@ int timeout = 5; unsigned char *tmpbuf; +#if 0 /*eeprom device address transfer*/ if(EEPROM_DEVICE_NUMBER == (device & 0xf0)){ device = device | ((sub_addr & 0x0700) >> 8); sub_addr = sub_addr & 0xff; } +#endif __i2c_send_nack(); /* Master does not send ACK, slave sends it */ W_try_again: @@ -251,8 +257,8 @@ ret = xfer_write(pmsg->addr, pmsg->buf, pmsg->len); } - if (ret) - return ret; + if (ret != pmsg->len) + return -1; /* Wait until transfer is finished */ } dev_dbg(&adap->dev, "transfer complete\n"); @@ -277,7 +283,9 @@ struct jz_i2c *i2c; struct i2c_jz_platform_data *plat = dev->dev.platform_data; int ret; +#ifndef CONFIG_SOC_JZ4730 __gpio_as_i2c(); // open i2c 20091027 +#endif __i2c_set_clk(jz_clocks.extalclk, 10000); /* default 10 KHz */ __i2c_enable(); _______________________________________________ Mipsbook-devel mailing list Mipsbook-devel@linuxtogo.org http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/mipsbook-devel
