Messages in this thread |  | | | Date | Mon, 7 Jun 2010 16:05:15 +0100 | | From | Alan Cox <> | | Subject | Re: [PATCH] Topcliff PHUB: Generate PacketHub driver |
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O> +/* Status Register offset */ > +#define PHUB_STATUS (0x00) > +/* Control Register offset */ > +#define PHUB_CONTROL (0x04) > +/* Time out value for Status Register */ > +#define PHUB_TIMEOUT (0x05) > +/* Enabling for writing ROM */ > +#define PCH_PHUB_ROM_WRITE_ENABLE (0x01) > +/* Disabling for writing ROM */ > +#define PCH_PHUB_ROM_WRITE_DISABLE (0x00) > +/* ROM data area start address offset */ > +#define PCH_PHUB_ROM_START_ADDR (0x14) > +/* MAX number of INT_REDUCE_CONTROL registers */ > +#define MAX_NUM_INT_REDUCE_CONTROL_REG (128) > + > +#define PCI_DEVICE_ID_PCH1_PHUB (0x8801) > + > +#define PCH_MINOR_NOS (1) > +#define CLKCFG_CAN_50MHZ (0x12000000) > +#define CLKCFG_CANCLK_MASK (0xFF000000) Style: constants don't need brackets - might also look more Linux like tabbed out a bit
> +#define PCH_READ_REG(a) ioread32((pch_phub_base_address + a)) > + > +#define PCH_WRITE_REG(a, b) iowrite32(a, (pch_phub_base_address + b))
These on the other hand do - but not where they are now
iowrite32((a), pcb_phub_base_address + (b))
(so that if a or b are expressions they are evaluated first)
> +struct pch_phub_reg { > + u32 phub_id_reg; /* PHUB_ID register val */ > + u32 q_pri_val_reg; /* QUEUE_PRI_VAL register val */ > + u32 rc_q_maxsize_reg; /* RC_QUEUE_MAXSIZE register val */ > + u32 bri_q_maxsize_reg; /* BRI_QUEUE_MAXSIZE register val */ > + u32 comp_resp_timeout_reg; /* COMP_RESP_TIMEOUT register val */ > + u32 bus_slave_control_reg; /* BUS_SLAVE_CONTROL_REG register val */ > + u32 deadlock_avoid_type_reg; /* DEADLOCK_AVOID_TYPE register val */ > + u32 intpin_reg_wpermit_reg0; /* INTPIN_REG_WPERMIT register 0 val */ > + u32 intpin_reg_wpermit_reg1; /* INTPIN_REG_WPERMIT register 1 val */ > + u32 intpin_reg_wpermit_reg2; /* INTPIN_REG_WPERMIT register 2 val */ > + u32 intpin_reg_wpermit_reg3; /* INTPIN_REG_WPERMIT register 3 val */ > + /* INT_REDUCE_CONTROL registers val */ > + u32 int_reduce_control_reg[MAX_NUM_INT_REDUCE_CONTROL_REG]; > +#ifdef PCH_CAN_PCLK_50MHZ > + u32 clkcfg_reg; /* CLK CFG register val */ > +#endif > +} g_pch_phub_reg;
Stylewise the kernel doesn't use the g_ convention that many Windows people do, so lose the g_
> +s32 pch_phub_opencount; /* check whether opened or not */ > +u32 pch_phub_base_address; > +u32 pch_phub_extrom_base_address; > +s32 pch_phub_suspended;
Any reason these can't be in the struct ? > + > +struct device *dev_dbg;
Not a good name for a global variable as it will clash with others
> +DEFINE_SPINLOCK(pch_phub_lock); /* for spin lock */
Can this be static or in the struct ?
> + > +/** > + * file_operations structure initialization > + */ > +const struct file_operations pch_phub_fops = { > + .owner = THIS_MODULE, > + .open = pch_phub_open, > + .release = pch_phub_release, > + .ioctl = pch_phub_ioctl, > +};
static const ?
> +/*-------------------------------------------- > + exported function prototypes > +--------------------------------------------*/
They start 'static' I don't think they are exportdd !
> +static int __devinit pch_phub_probe(struct pci_dev *pdev, const > + struct pci_device_id *id); > +static void __devexit pch_phub_remove(struct pci_dev *pdev); > +static int pch_phub_suspend(struct pci_dev *pdev, pm_message_t state); > +static int pch_phub_resume(struct pci_dev *pdev);
> +static struct pci_driver pch_phub_driver = { > + .name = "pch_phub", > + .id_table = pch_phub_pcidev_id, > + .probe = pch_phub_probe, > + .remove = __devexit_p(pch_phub_remove), > +#ifdef CONFIG_PM > + .suspend = pch_phub_suspend, > + .resume = pch_phub_resume > +#endif > +}; > + > +static int __init pch_phub_pci_init(void); > +static void __exit pch_phub_pci_exit(void); > + > +MODULE_DESCRIPTION("PCH PACKET HUB PCI Driver"); > +MODULE_LICENSE("GPL"); > +module_init(pch_phub_pci_init); > +module_exit(pch_phub_pci_exit); > +module_param(pch_phub_major_no, int, S_IRUSR | S_IWUSR);
If you migrated the module registration/PCI registration to the bottom of the file you could avoid the forward declations and make the code easier to follow ?
> +void pch_phub_read_modify_write_reg(unsigned long reg_addr_offset, > + unsigned long data, unsigned long mask) > +{ > + unsigned long reg_addr = pch_phub_base_address + reg_addr_offset; > + iowrite32(((ioread32((void __iomem *)reg_addr) & ~mask)) | data, > + (void __iomem *)reg_addr);
When you have that many casts in a line it's perhaps a hint you have the types wrong initially. At the very least reg_addr should be void __iomem, and probably pch_phub_base_address should be
It would probably make sense to pass a pointer to your struct pch_hub_reg and use that to hold the base address. Then if you ever get a box with two in some future design it won't be a disaster
> +void pch_phub_save_reg_conf(void)
Ditto
> +#ifdef PCH_CAN_PCLK_50MHZ > + /* save clk cfg register */ > + g_pch_phub_reg.clkcfg_reg = PCH_READ_REG(CLKCFG_REG_OFFSET); > +#endif
This makes it hard to build one kernel for everything
> + return; > +}
> +void pch_phub_restore_reg_conf(void) > +{ > + u32 i = 0;
Why = 0, if you do that here you may hide initialisation errors from future changes ?
> +/** pch_phub_read_serial_rom - Implements the functionality of reading Serial > + * ROM. > + * @offset_address: Contains the Serial ROM address offset value > + * @data: Contains the Serial ROM value > + */ > +int pch_phub_read_serial_rom(unsigned long offset_address, unsigned char *data) > +{ > + unsigned long mem_addr = pch_phub_extrom_base_address + offset_address; > + > + dev_dbg(dev_dbg, > + "pch_phub_read_serial_rom:mem_addr=0x%08x\n", (u32)mem_addr); > + *data = ioread8((void __iomem *)mem_addr);
Same comments about casts
> +int pch_phub_ioctl(struct inode *inode, struct file *file, > + unsigned int cmd, unsigned long arg) > +{ > + int ret_value = 0; > + struct pch_phub_reqt *p_pch_phub_reqt; > + unsigned long addr_offset;
This will change size on 32/64bit boxes makign your copy a bit problematic
> + p_pch_phub_reqt = (struct pch_phub_reqt *)arg; > + ret_value = copy_from_user((void *)&addr_offset, > + (void *)&p_pch_phub_reqt->addr_offset, > + sizeof(addr_offset)); > + if (ret_value) {
> + /* End of Access area check */
Remember here ioctl isn't single threaded so you may want to double check some of these
> +struct pch_phub_reqt { > + unsigned long addr_offset; /*specifies the register address > + offset */ > + unsigned long data; /*specifies the data */ > + unsigned long mask; /*specifies the mask */
If they may need to be long make them u64. That way 32 and 64bit systems get the same ioctl structure and life is good.
> +}; > + > +/* exported function prototypes */ > +int pch_phub_open(struct inode *inode, struct file *file); > +int pch_phub_release(struct inode *inode, struct file *file); > +int pch_phub_ioctl(struct inode *inode, struct file *file, unsigned int cmd, > + unsigned long arg);
You have various other functions that are not static - if they should be then make them static
Alan
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