Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753039Ab0LFEmS (ORCPT ); Sun, 5 Dec 2010 23:42:18 -0500 Received: from dsl78-143-211-26.in-addr.fast.co.uk ([78.143.211.26]:33242 "EHLO ben-laptop" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752438Ab0LFEmR (ORCPT ); Sun, 5 Dec 2010 23:42:17 -0500 Message-ID: <4CFC698D.2060703@fluff.org> Date: Mon, 06 Dec 2010 04:41:49 +0000 From: Ben Dooks User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.15) Gecko/20101027 Thunderbird/3.0.10 MIME-Version: 1.0 To: Tomoya MORINAGA CC: "Jean Delvare (PC drivers, core)" , "Ben Dooks (embedded platforms)" , Samuel Ortiz , Linus Walleij , Wolfram Sang , Ralf Baechle , srinidhi kasagar , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, qi.wang@intel.com, andrew.chih.howe.khor@intel.com, yong.y.wang@intel.com, kok.howg.ewe@intel.com Subject: Re: [PATCH] EG20T: Update PCH_I2C driver to 2.6.36 References: <4CD8CD32.5000909@dsn.okisemi.com> In-Reply-To: <4CD8CD32.5000909@dsn.okisemi.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15004 Lines: 562 On 09/11/10 04:25, Tomoya MORINAGA wrote: > Hi Jean, > > I have got Intel's signature. > Please push it to kernel tree. The description of the patch should go here, and I need a proper subject line for the commit. Comments like these go below the --- line. > Thanks, > Tomoya MORINAGA(OKI SEMICONDUCTOR CO., LTD.) > --- > I2C driver of EG20T PCH > > EG20T PCH is the platform controller hub that is going to be used in > Intel's upcoming general embedded platform. All IO peripherals in > EG20T PCH are actually devices sitting on AMBA bus. > EG20T PCH has I2C I/F. Using this I/F, it is able to access system > devices connected to I2C. > > Signed-off-by: Tomoya MORINAGA > Reviewed-by: Linus Walleij > Signed-off-by: Qi Wang > --- > drivers/i2c/busses/Kconfig | 8 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-eg20t.c | 900 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 909 insertions(+), 0 deletions(-) > create mode 100644 drivers/i2c/busses/i2c-eg20t.c > > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > index c3ef492..e55e051 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -60,6 +60,7 @@ obj-$(CONFIG_I2C_STU300) += i2c-stu300.o > obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o > obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o > obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o > +obj-$(CONFIG_I2C_EG20T) += i2c-eg20t.o Jean, do you want these alphabetically sorted? > # External I2C/SMBus adapter drivers > obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o > diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c > new file mode 100644 > index 0000000..f835635 > --- /dev/null > +++ b/drivers/i2c/busses/i2c-eg20t.c > @@ -0,0 +1,900 @@ [snip] > +/** > + * struct adapter_info - This structure holds the adapter information for the > + PCH i2c controller > + * @pch_data: stores a list of i2c_algo_pch_data > + * @pch_i2c_suspended: specifies whether the system is suspended or not > + * perhaps with more lines and words. you don't need the 'or not' and the extra line does not make sense? > + * > + * pch_data has as many elements as maximum I2C channels > + */ > +struct adapter_info { > + struct i2c_algo_pch_data pch_data; > + bool pch_i2c_suspended; > +}; > + > + > +static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */ > +static int pch_clk = 50000; /* specifies I2C clock speed in KHz */ > +static wait_queue_head_t pch_event; > +static DEFINE_MUTEX(pch_mutex); > + > +static struct pci_device_id __devinitdata pch_pcidev_id[] = { > + {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_PCH_I2C)}, > + {0,} please put single space after the { and before the }. > +static irqreturn_t pch_i2c_handler(int irq, void *pData); > + > +static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask) > +{ > + u32 val; > + val = ioread32(addr + offset); > + val |= bitmask; > + iowrite32(val, addr + offset); > +} > + > +static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask) > +{ > + u32 val; > + val = ioread32(addr + offset); > + val &= (~bitmask); the () around bitmask is useless. > + iowrite32(val, addr + offset); > +} > +static inline bool ktime_lt(const ktime_t cmp1, const ktime_t cmp2) > +{ > + return cmp1.tv64 < cmp2.tv64; > +} hmm, surely this sort of thing should be in a header somewhere? > +/** > + * pch_i2c_getack() - to confirm ACK/NACK > + * @adap: Pointer to struct i2c_algo_pch_data. > + */ > +static s32 pch_i2c_getack(struct i2c_algo_pch_data *adap) > +{ > + u32 reg_val; > + void __iomem *p = adap->pch_base_address; would prefer a blank line here also prefernece for longer items first in the list neither of these is really important though. > + reg_val = ioread32(p + PCH_I2CSR) & PCH_GETACK; > + > + if (reg_val != 0) { would (reg_val & PCH_GETACK) do here? > + pch_err(adap, "return%d\n", -EPROTO); > + return -EPROTO; > + } > + > + return 0; > +} > + > +/** > + * pch_i2c_writebytes() - write data to I2C bus in normal mode > + * @i2c_adap: Pointer to the struct i2c_adapter. > + * @last: specifies whether last message or not. > + * In the case of compound mode it will be 1 for last message, > + * otherwise 0. > + * @first: specifies whether first message or not. > + * 1 for first message otherwise 0. > + */ > +static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, > + struct i2c_msg *msgs, u32 last, u32 first) > +{ > + struct i2c_algo_pch_data *adap = i2c_adap->algo_data; > + u8 *buf; > + u32 length; > + u32 addr; > + u32 addr_2_msb; > + u32 addr_8_lsb; > + s32 wrcount; > + void __iomem *p = adap->pch_base_address; > + length = msgs->len; > + buf = msgs->buf; > + addr = msgs->addr; minor, these could have been merged with the declaration. > + /* enable master tx */ > + pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); > + > + pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL), > + length); > + > + if (first) { > + if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) > + return -ETIME; > + } > + > + if (msgs->flags & I2C_M_TEN) { > + addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7); > + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); > + if (first) > + pch_i2c_start(adap); > + if (pch_i2c_wait_for_xfer_complete(adap) == 0 && > + pch_i2c_getack(adap) == 0) { > + addr_8_lsb = (addr & I2C_ADDR_MSK); > + iowrite32(addr_8_lsb, p + PCH_I2CDR); > + } else { > + pch_i2c_stop(adap); > + return -ETIME; I'll have to check the error codes here, thought ETIMEDOUT would be better, or -EBUSY. > + } > + > + if ((pch_i2c_wait_for_xfer_complete(adap) == 0) && > + (pch_i2c_getack(adap) == 0)) { > + for (wrcount = 0; wrcount < length; ++wrcount) { > + /* write buffer value to I2C data register */ > + iowrite32(buf[wrcount], p + PCH_I2CDR); > + pch_dbg(adap, "writing %x to Data register\n", > + buf[wrcount]); > + > + if (pch_i2c_wait_for_xfer_complete(adap) != 0) > + return -ETIME; see above. > + if (pch_i2c_getack(adap)) > + return -EIO; > + } > + > + /* check if this is the last message */ > + if (last) > + pch_i2c_stop(adap); > + else > + pch_i2c_repstart(adap); > + } else { > + pch_i2c_stop(adap); > + return -EIO; > + } > + > + pch_dbg(adap, "return=%d\n", wrcount); > + > + return wrcount; > +} > + > +/** > + * pch_i2c_readbytes() - read data from I2C bus in normal mode. > + * @i2c_adap: Pointer to the struct i2c_adapter. > + * @msgs: Pointer to i2c_msg structure. > + * @last: specifies whether last message or not. > + * @first: specifies whether first message or not. > + */ > +s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, > + u32 last, u32 first) > +{ > + struct i2c_algo_pch_data *adap = i2c_adap->algo_data; > + > + u8 *buf; > + u32 count; > + u32 length; > + u32 addr; > + u32 addr_2_msb; > + void __iomem *p = adap->pch_base_address; > + > + length = msgs->len; > + buf = msgs->buf; > + addr = msgs->addr; > + > + /* enable master reception */ > + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); > + > + if (first) { > + if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) > + return -ETIME; > + } > + > + if (msgs->flags & I2C_M_TEN) { > + addr_2_msb = (((addr & I2C_MSB_2B_MSK) >> 7) | (I2C_RD)); > + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); > + > + } else { > + /* 7 address bits + R/W bit */ > + addr = (((addr) << 1) | (I2C_RD)); > + iowrite32(addr, p + PCH_I2CDR); > + } > + > + /* check if it is the first message */ > + if (first) > + pch_i2c_start(adap); > + > + if ((pch_i2c_wait_for_xfer_complete(adap) == 0) && > + (pch_i2c_getack(adap) == 0)) { > + pch_dbg(adap, "return %d\n", 0); > + > + if (length == 0) { > + pch_i2c_stop(adap); > + ioread32(p + PCH_I2CDR); /* Dummy read needs */ > + > + count = length; > + } else { > + int read_index; > + int loop; > + pch_i2c_sendack(adap); > + > + /* Dummy read */ > + for (loop = 1, read_index = 0; loop < length; loop++) { > + buf[read_index] = ioread32(p + PCH_I2CDR); > + > + if (loop != 1) > + read_index++; > + > + if (pch_i2c_wait_for_xfer_complete(adap) != 0) { > + pch_i2c_stop(adap); > + return -ETIME; don't think this is the correct return code here either.. > + } > + } /* end for */ > + > + pch_i2c_sendnack(adap); > + > + buf[read_index] = ioread32(p + PCH_I2CDR); > + > + if (length != 1) > + read_index++; > + > + if (pch_i2c_wait_for_xfer_complete(adap) == 0) { > + if (last) > + pch_i2c_stop(adap); > + else > + pch_i2c_repstart(adap); > + > + buf[read_index++] = ioread32(p + PCH_I2CDR); > + count = read_index; > + } else { > + count = -ETIME; > + } > + > + } > + } else { > + count = -ETIME; > + pch_i2c_stop(adap); > + } > + > + return count; > +} > + > + > +/** > + * pch_i2c_disbl_int() - Disable PCH I2C interrupts > + * @adap: Pointer to struct i2c_algo_pch_data. > + */ > +static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap) > +{ > + void __iomem *p = adap->pch_base_address; > + > + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL); > + > + iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK); > + could avoid blank here. > + iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK); > +} > + > +static int __devinit pch_i2c_probe(struct pci_dev *pdev, > + const struct pci_device_id *id) > +{ > + void __iomem *base_addr; > + s32 ret; > + struct adapter_info *adap_info; > + > + pch_pci_dbg(pdev, "Entered.\n"); > + > + adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL); extra () in here > + if (adap_info == NULL) { > + pch_pci_err(pdev, "Memory allocation FAILED\n"); > + return -ENOMEM; > + } do not need to capitalise 'FAILED' > + > + ret = pci_enable_device(pdev); > + if (ret) { > + pch_pci_err(pdev, "pci_enable_device FAILED\n"); > + goto err_pci_enable; > + } () after pci_device_enable... also see previous. > + > + ret = pci_request_regions(pdev, KBUILD_MODNAME); how about using dev_name() in case of multiple devices. > + if (ret) { > + pch_pci_err(pdev, "pci_request_regions FAILED\n"); > + goto err_pci_req; > + } > + > + base_addr = pci_iomap(pdev, 1, 0); > + > + if (base_addr == NULL) { > + pch_pci_err(pdev, "pci_iomap FAILED\n"); > + ret = -ENOMEM; > + goto err_pci_iomap; > + } > + > + adap_info->pch_i2c_suspended = false; > + > + adap_info->pch_data.p_adapter_info = adap_info; > + > + adap_info->pch_data.pch_adapter.owner = THIS_MODULE; > + adap_info->pch_data.pch_adapter.class = I2C_CLASS_HWMON; > + strcpy(adap_info->pch_data.pch_adapter.name, KBUILD_MODNAME); please use a string copy that limits transfer size.... > + adap_info->pch_data.pch_adapter.algo = &pch_algorithm; > + adap_info->pch_data.pch_adapter.algo_data = > + &adap_info->pch_data; > + > + /* (i * 0x80) + base_addr; */ > + adap_info->pch_data.pch_base_address = base_addr; > + > + adap_info->pch_data.pch_adapter.dev.parent = &pdev->dev; > + > + ret = i2c_add_adapter(&(adap_info->pch_data.pch_adapter)); > + > + if (ret) { > + pch_pci_err(pdev, "i2c_add_adapter FAILED\n"); > + goto err_i2c_add_adapter; > + } > + > + pch_i2c_init(&adap_info->pch_data); > + ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED, > + KBUILD_MODNAME, &adap_info->pch_data); see note on dev_name() > + if (ret) { > + pch_pci_err(pdev, "request_irq FAILED\n"); > + goto err_request_irq; > + } > + > + pci_set_drvdata(pdev, adap_info); > + pch_pci_dbg(pdev, "returns %d.\n", ret); > + return 0; > + > +err_request_irq: > + i2c_del_adapter(&(adap_info->pch_data.pch_adapter)); > +err_i2c_add_adapter: > + pci_iounmap(pdev, base_addr); > +err_pci_iomap: > + pci_release_regions(pdev); > +err_pci_req: > + pci_disable_device(pdev); > +err_pci_enable: > + kfree(adap_info); > + return ret; > +} > + > +static void __devexit pch_i2c_remove(struct pci_dev *pdev) > +{ > + struct adapter_info *adap_info = pci_get_drvdata(pdev); > + > + pch_i2c_disbl_int(&adap_info->pch_data); > + free_irq(pdev->irq, &adap_info->pch_data); > + i2c_del_adapter(&(adap_info->pch_data.pch_adapter)); > + > + if (adap_info->pch_data.pch_base_address) { > + pci_iounmap(pdev, adap_info->pch_data.pch_base_address); > + adap_info->pch_data.pch_base_address = 0; NULL, not 0 > + } > + > + pci_set_drvdata(pdev, NULL); > + > + pci_release_regions(pdev); > + > + pci_disable_device(pdev); > + kfree(adap_info); > +} > + > +#ifdef CONFIG_PM > +static int pch_i2c_suspend(struct pci_dev *pdev, pm_message_t state) > +{ > + int ret; > + struct adapter_info *adap_info = pci_get_drvdata(pdev); > + void __iomem *p = adap_info->pch_data.pch_base_address; > + > + adap_info->pch_i2c_suspended = true; > + > + while ((adap_info->pch_data.pch_i2c_xfer_in_progress)) { > + /* Wait until all channel transfers are completed */ > + msleep(20); > + } > + /* Disable the i2c interrupts */ > + pch_i2c_disbl_int(&adap_info->pch_data); > + > + pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x " > + "invoked function pch_i2c_disbl_int successfully\n", > + ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA), > + ioread32(p + PCH_I2CESRSTA)); > + > + ret = pci_save_state(pdev); > + > + if (ret) { > + pch_pci_err(pdev, "pci_save_state\n"); > + return ret; > + } > + > + pci_enable_wake(pdev, PCI_D3hot, 0); > + pci_disable_device(pdev); > + pci_set_power_state(pdev, pci_choose_state(pdev, state)); > + > + return 0; > +} > + > +static int pch_i2c_resume(struct pci_dev *pdev) > +{ > + struct adapter_info *adap_info = pci_get_drvdata(pdev); > + > + pci_set_power_state(pdev, PCI_D0); > + pci_restore_state(pdev); > + > + if (pci_enable_device(pdev) < 0) { > + pch_pci_err(pdev, "pch_i2c_resume:pci_enable_device FAILED\n"); > + return -EIO; > + } > + > + pci_enable_wake(pdev, PCI_D3hot, 0); > + > + pch_i2c_init(&adap_info->pch_data); > + > + adap_info->pch_i2c_suspended = false; > + > + return 0; > +} > +#else > +#define pch_i2c_suspend NULL > +#define pch_i2c_resume NULL > +#endif > + > +static struct pci_driver pch_pcidriver = { > + .name = KBUILD_MODNAME, > + .id_table = pch_pcidev_id, > + .probe = pch_i2c_probe, > + .remove = __devexit_p(pch_i2c_remove), > + .suspend = pch_i2c_suspend, > + .resume = pch_i2c_resume runtime PM would be better. > + > +MODULE_DESCRIPTION("PCH I2C PCI Driver"); > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Tomoya MORINAGA. "); > +module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR)); > +module_param(pch_clk, int, (S_IRUSR | S_IWUSR)); Please sort out as much as possible of the review comments. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/