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* i2c: i2c-mxs: Wait for I2C to empty queueMarek Vasut2014-02-20-7/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure the I2C write queue is empty before leaving the mxs_i2c_write(). If we start and I2C write and only wait for ACK, the MXS I2C IP block may enter next operation while still processing the write aftermath internally. This will in turn disrupt one or more subsequent transfer(s). A testcase for this issue is as such. This testcase is also interesting because the first I2C_WRITE which becomes disruptive happens in the 'i2c read' command. The 'i2c read' command first uses I2C_WRITE to send I2C address of the chip and then uses I2C_READ to read data from the chip. After this command completes, the 'i2c probe' will use sequence of I2C_WRITE commands to probe the I2C bus. The problem is that the first I2C_WRITE disrupted the I2C IP block operation and this sideeffect propagates all the way to this next I2C_WRITE used by the 'i2c probe' call. The result is the 'i2c probe' receives an ACK on I2C address 0x00, even if this ACK was owned by the previous I2C_WRITE operation. Note that the 'i2c read' command must read from a valid I2C chip address. Wrong: > i2c probe Valid chip addresses: 50 51 > i2c read 0x50 0x0.2 0x10 0x42000000 > i2c probe Valid chip addresses: 00 50 51 With this patch > i2c probe Valid chip addresses: 50 51 > i2c read 0x50 0x0.2 0x10 0x42000000 > i2c probe Valid chip addresses: 50 51 Signed-off-by: Marek Vasut <marex@denx.de> Cc: Heiko Schocher <hs@denx.de> Cc: Fabio Estevam <festevam@gmail.com>
* i2c: mxs_i2c: Squash endless loopMarek Vasut2013-11-13-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | | The endless waiting for a bit to be set can cause a hang, add a timeout so we prevent such situation. A testcase for such a hang is below. The testcase assumes a device to be present at address 0x50 and a device to NOT be present at address 0x42 . Also note that the "sleep 1" induced delays are imperative for this bug to manifest . i2c read 0x42 0x0.2 0x10 0x42000000 ; sleep 1 ; \ i2c read 0x50 0x0.2 0x10 0x42000000 ; sleep 1 ; \ i2c read 0x42 0x0.2 0x10 0x42000000 The expected result of the above command is: Error reading the chip. Error reading the chip. While without this patch, we observe a hang in the last read from 0x42 precisely when waiting for this bit to be set. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Heiko Schocher <hs@denx.de> Cc: Stefano Babic <sbabic@denx.de>
* Add GPL-2.0+ SPDX-License-Identifier to source filesWolfgang Denk2013-07-24-14/+1
| | | | | | Signed-off-by: Wolfgang Denk <wd@denx.de> [trini: Fixup common/cmd_io.c] Signed-off-by: Tom Rini <trini@ti.com>
* i2c: mxs: Staticize the functions in the driverMarek Vasut2013-01-29-4/+4
| | | | | | | | The local functions in the mxs i2c driver are not marked static, make it so. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Heiko Schocher <hs@denx.de>
* mxs: i2c: Implement algorithm to set up arbitrary i2c speedMarek Vasut2012-12-11-53/+34
| | | | | | | | | | | | | | | This algorithm computes the values of TIMING{0,1,2} registers for the MX28 I2C block. This algorithm was derived by using a scope, but the result seems correct. The resulting values programmed into the registers do not correlate with the contents in datasheet. When using the values from the datasheet, the I2C clock were completely wrong. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Wolfgang Denk <wd@denx.de>
* mxs: i2c: Restore speed setting after block resetMarek Vasut2012-12-11-0/+3
| | | | | | | | | | | | The I2C block reset configures the I2C bus speed to strange value. Read the I2C speed from the block before reseting the block and restore it afterwards, so the I2C operates correctly. This issue can be replicated by doing unsuccessful I2C transfer, after such transfer finishes, the I2C block clock speed is misconfigured. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Heiko Schocher <hs@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com>
* i2c: mxs: Fix TIMING2 register valueMarek Vasut2012-12-11-2/+2
| | | | | | | | | | | According to FSL, the value in the TIMING2 register shall be 0x00300030 instead of what's written in the datasheet. This new value correlates with older STMP36xx datasheet. Issues were detected in Linux when this register was misconfigured, so write this correct value. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com>
* i2c: mxs: Use i2c_set_bus_speed() in i2c_init()Marek Vasut2012-12-11-15/+1
| | | | | | | | | Use i2c_set_bus_speed() in i2c_init() within the mxs i2c driver to avoid duplication of code. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com>
* i2c: mxs: Implement i2c_get/set_bus_speed()Marek Vasut2012-12-11-0/+45
| | | | | | | | | This patch implements the setup and retrieval functions for the I2C bus speed on the MXS I2C IP. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com>
* i2c: mxs: Abstract out the MXS I2C speed setupMarek Vasut2012-12-11-20/+37
| | | | | | | | | | | | | | This patch pulls out the I2C speed setup from the i2c_init() call and implements the bus configuration lookup table with register values that needs to be programmed into the I2C IP to run at particular speed. This patch is a first step towards implementing run-time I2C bus speed configuration for the MXS I2C IP. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Fabio Estevam <fabio.estevam@freescale.com>
* mxs: Convert sys_proto.h prefixes to 'mxs'Otavio Salvador2012-09-01-1/+1
| | | | | | | The sys_proto.h functions (except the boot modes) are compatible with i.MX233 and i.MX28 so we use 'mxs' prefix for its methods. Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
* mxs: prefix register structs with 'mxs' prefixOtavio Salvador2012-09-01-6/+6
| | | | Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
* mxs-i2c: Fix internal address byte orderTorsten Fleischer2012-07-11-1/+1
| | | | | | | | | | | | | | | | | | Large EEPROMs, e.g. 24lc32, need 2 byte to address the internal memory. These devices require that the high byte of the internal address has to be written first. The mxs_i2c driver currently writes the address' low byte first. The following patch fixes the byte order of the internal address that should be written to the I2C device. Signed-off-by: Torsten Fleischer <to-fleischer@t-online.de> CC: Marek Vasut <marex@denx.de> CC: Stefano Babic <sbabic@denx.de> CC: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Marek Vasut <marex@denx.de> Acked-by: Stefano Babic <sbabic@denx.de>
* iMX28: Add I2C bus driverMarek Vasut2011-11-11-0/+246
Signed-off-by: Marek Vasut <marek.vasut@gmail.com> Cc: Heiko Schocher <hs@denx.de> Cc: Stefano Babic <sbabic@denx.de> Cc: Wolfgang Denk <wd@denx.de> Cc: Detlev Zundel <dzu@denx.de> Acked-by: Heiko Schocher<hs@denx.de>
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