Open Lukse opened 11 years ago
Quoting from the forum link above.
Hi,
I've been playing with the GPIOs on Carambola and observed that whenever I try to initialize a GPIO pin for the first time I'm getting a kernel warning like this:
[ 3012.360000] ------------[ cut here ]------------ [ 3012.360000] WARNING: at drivers/gpio/gpiolib.c:101 0x80116e94() [ 3012.360000] autorequest GPIO-11 [ 3012.360000] Modules linked in: usb_storage i2c_gpio i2c_algo_bit dwc_otg i2c_dev i2c_core nf_nat_irc nf_conntrack_irc nf_nat_ftp nf_conntrack_ftp ipt_MASQUERADE iptable_nat nf_nat pppoe xt_conntrack xt_CT xt_NOTRACK iptable_raw xt_state nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack sd_mod pppox ipt_REJECT xt_TCPMSS ipt_LOG xt_comment xt_multiport xt_mac xt_limit iptable_mangle iptable_filter ip_tables xt_tcpudp x_tables gpio_dev ppp_async ppp_generic slhc rt2800usb(O) rt2800pci(O) rt2800lib(O) rt2500usb(O) rt2x00usb(O) rt2x00soc(O) rt2x00pci(O) rt2x00lib(O) mac80211(O) lib80211_crypt_tkip(O) lib80211_crypt_ccmp(O) lib80211_crypt_wep(O) lib80211(O) usbcore usb_common scsi_mod nls_base crc_itu_t crc_ccitt eeprom_93cx6 cfg80211(O) compat(O) arc4 aes_generic crypto_algapi leds_gpio [ 3012.360000] Call Trace:[<801df038>] 0x801df038 [ 3012.360000] [<801df038>] 0x801df038 [ 3012.360000] [<80116e94>] 0x80116e94 [ 3012.360000] [<80010664>] 0x80010664 [ 3012.360000] [<80116e94>] 0x80116e94 [ 3012.360000] [<80010718>] 0x80010718 [ 3012.360000] [<80116e94>] 0x80116e94 [ 3012.360000] [<801170b0>] 0x801170b0 [ 3012.360000] [<800865ec>] 0x800865ec [ 3012.360000] [<80031a44>] 0x80031a44 [ 3012.360000] [<800872cc>] 0x800872cc [ 3012.360000] [<80031b40>] 0x80031b40 [ 3012.360000] [<8008f2c0>] 0x8008f2c0 [ 3012.360000] [<800343a0>] 0x800343a0 [ 3012.360000] [<80033b40>] 0x80033b40 [ 3012.360000] [<80047814>] 0x80047814 [ 3012.360000] [<80087370>] 0x80087370 [ 3012.360000] [<80008d30>] 0x80008d30 [ 3012.360000] [ 3012.360000] ---[ end trace b875ca21dcbec7a4 ]---
Looking into the kernel sources, I found out that this warning is issued when the board setup code > didn't call
gpio_request()
for that specific pin. In the board setup code, the function that should initialize the GPIO pins isrt305x_gpio_init(u32 mode)
:void __init rt305x_gpio_init(u32 mode) { u32 t; rt305x_sysc_wr(mode, SYSC_REG_GPIO_MODE); ramips_gpio_init(&rt305x_gpio_data); if ((mode & RT305X_GPIO_MODE_I2C) == 0) rt305x_gpio_reserve(RT305X_GPIO_I2C_SD, RT305X_GPIO_I2C_SCLK); if ((mode & RT305X_GPIO_MODE_SPI) == 0) rt305x_gpio_reserve(RT305X_GPIO_SPI_EN, RT305X_GPIO_SPI_DIN); t = mode >> RT305X_GPIO_MODE_UART0_SHIFT; t &= RT305X_GPIO_MODE_UART0_MASK; switch (t) { case RT305X_GPIO_MODE_UARTF: case RT305X_GPIO_MODE_PCM_UARTF: case RT305X_GPIO_MODE_PCM_I2S: case RT305X_GPIO_MODE_I2S_UARTF: rt305x_gpio_reserve(RT305X_GPIO_7, RT305X_GPIO_14); break; case RT305X_GPIO_MODE_PCM_GPIO: rt305x_gpio_reserve(RT305X_GPIO_10, RT305X_GPIO_14); break; case RT305X_GPIO_MODE_GPIO_UARTF: case RT305X_GPIO_MODE_GPIO_I2S: rt305x_gpio_reserve(RT305X_GPIO_7, RT305X_GPIO_10); break; } ...
Reading the code more carefully I observed that this function is not correct. What I mean is that for the UARTF, PCM_UARTF, PCM_I2S and I2S_UARTF modes the code shouldn't request any GPIO, while for PCM_GPIO it should request GPIOs 7, 8, 9, for GPIO_UARTF and GPIO_I2S it should request GPIOs 11, 12, 13, 14 and for RT305X_GPIO_MODE_GPIO (which is the default) it should request all GPIOs from 7 to 14.
I think the same observation applies to all the other tests (I2C, SPI, UART1, JTAG ...) where the conditions seem to be reversed too.
Due to formatting and long description I am submitting link to problem.
http://www.8devices.com/community/viewtopic.php?f=6&t=202
Please review.